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{"title": "Radio-Continuum Emission From The Young Galactic Supernova Remnant G1.9+0.3", "abstract": "We present an analysis of a new Australia Telescope Compact Array (ATCA) radio-continuum observation of supernova remnant (SNR) G1.9+0.3, which at an age of $\\sim$181$\\pm$25 years is the youngest known in the Galaxy. We analysed all available radio-continuum observations at 6-cm from the ATCA and the Very Large Array. Using this data we estimate an expansion rate for G1.9+0.3 of 0.563%$\\pm$0.078% per year between 1984 and 2009. We note that in the 1980's G1.9+0.3 expanded somewhat slower (0.484% per year) than more recently (0.641% per year). We estimate that the average spectral index between 20-cm and 6-cm, across the entire SNR is $\\alpha=-0.72\\pm 0.26$ which is typical for younger SNRs. At 6-cm, we detect an average of 6% fractionally polarised radio emission with a peak of 17%$\\pm$3%. The polarised emission follows the contours of the strongest of X-ray emission. Using the new equipartition formula we estimate a magnetic field strength of B$\\approx 273\\mu$G, which to date, is one of the highest magnetic field strength found for any SNR and consistent with G1.9+0.3 being a very young remnant. This magnetic field strength implies a minimum total energy of the synchrotron radiation of E$_{\\textrm{min}} \\approx$ 1.8$\\times$10$^{48}$ ergs.", "tagged_title": "<object>Radio-Continuum Emission</object> From The Young <object>Galactic Supernova Remnant G1.9+0.3</object>", "tagged_abstract": "We present an analysis of a new <dataset><instrument>Australia Telescope Compact Array (ATCA)</instrument> <modality>radio-continuum</modality> observation</dataset> of <object>supernova remnant (SNR) G1.9+0.3</object>, which at an <property>age</property> of $\\sim$181$\\pm$25 years is the youngest known in the <object>Galaxy</object>. We analysed all available <dataset><modality>radio-continuum</modality> observations</dataset at 6-cm from the <instrument>ATCA</instrument> and the <instrument>Very Large Array</instrument>. Using this data we estimate an <property>expansion rate</property> for <object>G1.9+0.3</object> of 0.563%$\\pm$0.078% per year between 1984 and 2009. We note that in the 1980's <object>G1.9+0.3</object> expanded somewhat slower (0.484% per year) than more recently (0.641% per year). We estimate that the <property>average spectral index</property> between 20-cm and 6-cm, across the entire <object>SNR</object> is $\\alpha=-0.72\\pm 0.26$ which is typical for younger <object>SNRs</object>. At 6-cm, we detect an average of 6% fractionally polarised <object>radio emission</object> with a peak of 17%$\\pm$3%. The <object>polarised emission</object> follows the contours of the strongest of <object>X-ray emission</object>. Using the new <method>equipartition formula</method> we estimate a <property>magnetic field strength</property> of B$\\approx 273\\mu$G, which to date, is one of the highest <property>magnetic field strength</property> found for any <object>SNR</object> and consistent with <object>G1.9+0.3</object> being a very young <object>remnant</object>. This <property>magnetic field strength</property> implies a minimum total <property>energy</property> of the <object>synchrotron radiation</object> of E$_{\\textrm{min}} \\approx$ 1.8$\\times$10$^{48}$ ergs.", "tagged_phrases": {"object": ["Radio-Continuum Emission", "Galactic Supernova Remnant G1.9+0.3", "supernova remnant (SNR) G1.9+0.3", "Galaxy", "G1.9+0.3", "SNR", "SNRs", "radio emission", "polarised emission", "X-ray emission", "remnant", "synchrotron radiation"], "dataset": ["Australia Telescope Compact Array (ATCA) radio-continuum observation", "radio-continuum observations"], "instrument": ["Australia Telescope Compact Array (ATCA)", "Very Large Array"], "modality": ["radio-continuum"], "property": ["age", "expansion rate", "average spectral index", "magnetic field strength", "energy"], "method": ["equipartition formula"]}}
{"title": "Trispectrum versus Bispectrum in Single-Field Inflation", "abstract": "In the standard slow-roll inflationary cosmology, quantum fluctuations in a single field, the inflaton, generate approximately Gaussian primordial density perturbations. At present, the bispectrum and trispectrum of the density perturbations have not been observed and the probability distribution for these perturbations is consistent with Gaussianity. However, Planck satellite data will bring a new level of precision to bear on this issue, and it is possible that evidence for non-Gaussian effects in the primordial distribution will be discovered. One possibility is that a trispectrum will be observed without evidence for a non-zero bispectrum. It is not difficult for this to occur in inflationary models where quantum fluctuations in a field other than the inflaton contribute to the density perturbations. A natural question to ask is whether such an observation would rule out the standard scenarios. We explore this issue and find that it is possible to construct single-field models in which inflaton-generated primordial density perturbations have an observable trispectrum, but a bispectrum that is too small to be observed by the Planck satellite. However, an awkward fine tuning seems to be unavoidable.", "tagged_title": "<property>Trispectrum</property> versus <property>Bispectrum</property> in <object>Single-Field Inflation</object>", "tagged_abstract": "In the standard <model>slow-roll inflationary <field>cosmology</field></model>, <object>quantum fluctuations</object> in a single <object>field</object>, the <object>inflaton</object>, generate approximately <property>Gaussian</property> <property>primordial</property> <object><modality>density</modality> perturbations</object>. At present, the <property>bispectrum</property> and <property>trispectrum</property> of the <object><modality>density</modality> perturbations</object> have not been observed and the probability distribution for these <object>perturbations</object> is consistent with <property>Gaussianity</property>. However, <dataset><instrument>Planck satellite</instrument> data</dataset> will bring a new level of precision to bear on this issue, and it is possible that evidence for <property>non-Gaussian</property> effects in the <object>primordial distribution</object> will be discovered. One possibility is that a <property>trispectrum</property> will be observed without evidence for a non-zero <property>bispectrum</property>. It is not difficult for this to occur in <model>inflationary models</model> where <object>quantum fluctuations</object> in a field other than the <object>inflaton</object> contribute to the <object><modality>density</modality> perturbations</object>. A natural question to ask is whether such an observation would rule out the standard scenarios. We explore this issue and find that it is possible to construct <model>single-field models</model> in which <property>inflaton-generated</property> <property>primordial</property> <object><modality>density</modality> perturbations</object> have an observable <property>trispectrum</property>, but a <property>bispectrum</property> that is too small to be observed by the <instrument>Planck satellite</instrument>. However, an awkward fine tuning seems to be unavoidable.", "tagged_phrases": {"property": ["Trispectrum", "Bispectrum", "Gaussian", "primordial", "bispectrum", "trispectrum", "Gaussianity", "non-Gaussian", "inflaton-generated"], "object": ["Single-Field Inflation", "quantum fluctuations", "field", "inflaton", "density perturbations", "perturbations", "primordial distribution"], "model": ["slow-roll inflationary cosmology", "inflationary models", "single-field models"], "field": ["cosmology"], "modality": ["density"], "dataset": ["Planck satellite data"], "instrument": ["Planck satellite"]}}
{"title": "A differential study of the oxygen abundances in the Galactic thin and thick disks", "abstract": "First results from a study into the abundance trends of oxygen in the Galactic thin and thick disks are presented. Oxygen abundances for 63 nearby F and G dwarf stars, based on very high resolution spectra ($R\\sim215 000$) and high signal-to-noise ($S/N>400$) of the faint forbidden oxygen line at 6300 {\\AA}, have been determined. Our findings can be summarized as follows: {\\bf 1)} at $\\rm [Fe/H]<0$ the oxygen trends in the thin and thick disk are smooth and distinct, indicating their different origins, {\\bf 2)} $\\rm [O/Fe]$ for the thick disk stars show a turn-over at [Fe/H]$\\sim -0.35$, indicating the peak of the enrichment from SNe type Ia to the interstellar medium, {\\bf 3)} the thin disk stars show a shallow decrease going from $\\rm [Fe/H] \\sim -0.7$ to the highest metallicities with no apparent turn-over present indicating a more quiet star formation history, and {\\bf 4)} $\\rm [O/Fe]$ continues to decrease at $\\rm [Fe/H]>0$ without showing the leveling out that previously has been seen.", "tagged_title": "A differential study of the <object><object>oxygen</object> abundances</object> in the Galactic <property>thin</property> and <property>thick</property> <object>disks</object>", "tagged_abstract": "First results from a study into the <property>abundance trends</property> of <object>oxygen</object> in the Galactic <property>thin</property> and <property>thick</property> <object>disks</object> are presented. <object><object>Oxygen</object> abundances</object> for 63 nearby <object>F</object> and <object>G</object> <object>dwarf stars</object>, based on very high resolution <modality>spectra</modality> (R~215000) and high <property>signal-to-noise</property> (S/N>400) of the faint forbidden <object>oxygen line</object> at 6300 \u00c5, have been determined. Our findings can be summarized as follows: {\\bf 1)} at [Fe/H] < 0 the <object><object>oxygen</object> trends</object> in the <property>thin</property> and <property>thick</property> <object>disk</object> are smooth and distinct, indicating their different origins, {\\bf 2)} [O/Fe] for the <object><property>thick disk</property> stars</object> show a turn-over at [Fe/H] ~ \u22120.35, indicating the peak of the enrichment from SNe type Ia to the <object>interstellar medium</object>, {\\bf 3)} the <object><property>thin disk</property> stars</object> show a shallow decrease going from [Fe/H] ~ \u22120.7 to the highest <property>metallicities</property> with no apparent turn-over present indicating a more quiet <object>star</object> formation history, and {\\bf 4)} [O/Fe] continues to decrease at [Fe/H] > 0 without showing the leveling out that previously has been seen.", "tagged_phrases": {"object": ["oxygen abundances", "oxygen", "disks", "Oxygen abundances", "Oxygen", "F", "G", "dwarf stars", "oxygen line", "oxygen trends", "disk", "thick disk stars", "interstellar medium", "thin disk stars", "star"], "property": ["thin", "thick", "abundance trends", "signal-to-noise", "thick disk", "thin disk", "metallicities"], "modality": ["spectra"]}}
{"title": "The radiative transfer at second order: a full treatment of the Boltzmann equation with polarization", "abstract": "This article investigates the full Boltzmann equation up to second order in the cosmological perturbations. Describing the distribution of polarized radiation by a tensor valued distribution function, we study the gauge dependence of the distribution function and summarize the construction of the gauge-invariant distribution function. The Liouville operator which describes the free streaming of electrons, and the collision term which describes the scattering of photons on free electrons are computed up to second order. Finally, the remaining dependence in the direction of the photon momentum is handled by expanding in projected symmetric trace-free multipoles and also in the more commonly used normal modes components. The results obtained remain to be used for computing numerically the contribution in the cosmic microwave background bispectrum which arises from the evolution of second order perturbations, in order to disentangle the primordial non-Gaussianity from the one generated by the subsequent non-linear evolution.", "tagged_title": "The <object>radiative transfer at second order</object>: a full treatment of the <method>Boltzmann equation</method> with polarization", "tagged_abstract": "This article investigates the full <method>Boltzmann equation</method> up to second order in the <object><field>cosmological</field> perturbations</object>. Describing the distribution of <object>polarized radiation</object> by a <method>tensor valued distribution function</method>, we study the <property>gauge dependence</property> of the <method>distribution function</method> and summarize the construction of the <method><property>gauge-invariant</property> distribution function</method>. The <model>Liouville operator</model> which describes the free streaming of <object>electrons</object>, and the <object>collision term</object> which describes the <object>scattering of photons</object> on <object>free electrons</object> are computed up to second order. Finally, the remaining <property>dependence</property> in the direction of the <object>photon</object> <property>momentum</property> is handled by expanding in projected <property>symmetric</property> <property>trace-free</property> <object>multipoles</object> and also in the more commonly used <object>normal modes components</object>. The results obtained remain to be used for computing numerically the contribution in the <object>cosmic microwave background <property>bispectrum</property></object> which arises from the evolution of <object>second order perturbations</object>, in order to disentangle the <property>primordial non-Gaussianity</property> from the one generated by the subsequent <object><property>non-linear</property> evolution</object>.", "tagged_phrases": {"object": ["radiative transfer at second order", "cosmological perturbations", "polarized radiation", "electrons", "collision term", "scattering of photons", "free electrons", "photon", "multipoles", "normal modes components", "cosmic microwave background bispectrum", "second order perturbations", "non-linear evolution"], "method": ["Boltzmann equation", "tensor valued distribution function", "distribution function", "gauge-invariant distribution function"], "field": ["cosmological"], "property": ["gauge dependence", "gauge-invariant", "dependence", "momentum", "symmetric", "trace-free", "bispectrum", "primordial non-Gaussianity", "non-linear"], "model": ["Liouville operator"]}}
{"title": "Independent confirmation and refined parameters of the hot Jupiter XO-5b", "abstract": "We present HATNet observations of XO-5b, confirming its planetary nature based on evidence beyond that described in the announcement of Burke et al. (2008), namely, the lack of significant correlation between spectral bisector variations and orbital phase. In addition, using extensive spectroscopic measurements spanning multiple seasons, we investigate the relatively large scatter in the spectral line bisectors. We also examine possible blended stellar configurations (hierarchical triples, chance alignments) that can mimic the planet signals, and we are able to show that none are consistent with the sum of all the data. The analysis of the S activity index shows no significant stellar activity. Our results for the planet parameters are consistent with values in Burke et al. (2008), and we refine both the stellar and planetary parameters using our data. XO-5b orbits a slightly evolved, late G type star with mass M_s = 0.88 +/- 0.03, radius R_s = 1.08 +/- 0.04, and metallicity close to solar. The planetary mass and radius are M_p = 1.059 +/- 0.028 M_Jup and R_p = 1.109 +/- 0.050 R_Jup, respectively, corresponding to a mean density of 0.96 -0.11 +0.14 g/cm^3. The ephemeris for the orbit is P = 4.187757 +/- 0.000011, E= 2454552.67168 +/- 0.00029 (BJD) with transit duration of 0.1307 +/- 0.0013 d. By measuring four individual transit centers, we found no signs for transit timing variations. The planet XO-5b is notable for its anomalously high Safronov number, and has a high surface gravity when compared to other transiting exoplanets with similar period.", "tagged_title": "Independent confirmation and refined parameters of the hot <object>Jupiter XO-5b</object>", "tagged_abstract": "We present <dataset><instrument>HATNet</instrument> observations</dataset> of <object>XO-5b</object>, confirming its planetary nature based on evidence beyond that described in the announcement of Burke et al. (2008), namely, the lack of significant <property>correlation</property> between <property>spectral bisector variations</property> and <property>orbital phase</property>. In addition, using extensive <modality>spectroscopic measurements</modality> spanning multiple seasons, we investigate the relatively large <property>scatter</property> in the <property>spectral line bisectors</property>. We also examine possible blended <object>stellar configurations</object> (<object>hierarchical triples</object>, <object>chance alignments</object>) that can mimic the <object>planet signals</object>, and we are able to show that none are consistent with the sum of all the data. The analysis of the <property>S activity index</property> shows no significant <object>stellar activity</object>. Our results for the <object>planet parameters</object> are consistent with values in Burke et al. (2008), and we refine both the <object>stellar and planetary parameters</object> using our data. <object>XO-5b</object> orbits a slightly evolved, late <object>G type star</object> with <property>mass</property> <property>M_s</property> = 0.88 +/- 0.03, <property>radius</property> <property>R_s</property> = 1.08 +/- 0.04, and <property>metallicity</property> close to solar. The planetary <property>mass</property> and <property>radius</property> are <property>M_p</property> = 1.059 +/- 0.028 M_Jup and <property>R_p</property> = 1.109 +/- 0.050 R_Jup, respectively, corresponding to a <property>mean density</property> of 0.96 -0.11 +0.14 g/cm^3. The <property>ephemeris</property> for the <property>orbit</property> is <property>P</property> = 4.187757 +/- 0.000011, <property>E</property> = 2454552.67168 +/- 0.00029 (BJD) with <property>transit duration</property> of 0.1307 +/- 0.0013 d. By measuring four individual transit centers, we found no signs for <object>transit timing variations</object>. The planet <object>XO-5b</object> is notable for its anomalously high <property>Safronov number</property>, and has a high surface <property>gravity</property> when compared to other transiting <object>exoplanets</object> with similar period.", "tagged_phrases": {"object": ["Jupiter XO-5b", "XO-5b", "stellar configurations", "hierarchical triples", "chance alignments", "planet signals", "stellar activity", "planet parameters", "stellar and planetary parameters", "G type star", "transit timing variations", "exoplanets"], "dataset": ["HATNet observations"], "instrument": ["HATNet"], "property": ["correlation", "spectral bisector variations", "orbital phase", "scatter", "spectral line bisectors", "S activity index", "mass", "M_s", "radius", "R_s", "metallicity", "M_p", "R_p", "mean density", "ephemeris", "orbit", "P", "E", "transit duration", "Safronov number", "gravity"], "modality": ["spectroscopic measurements"]}}
{"title": "Electron Temperatures in W51 Complex from High Resolution, Low Frequency Radio Observations", "abstract": "W51 is a giant radio complex lying along the tangent to the Sagitarius arm at a distance of about 7kpc from Sun, with an extension of about 1deg in the sky. It is divided into three components A,B,C where W51A and W51B consist of many compact HII regions while W51C is a supernova remnant. We have made continuum radio observations of these HII regions of the W51 complex at 240,610,1060,1400 MHz using GMRT with lower resolution 20''x15'' at the lowest frequency. The observed spectra of the prominent thermal subcomponents of W51 have been fitted to a free-free emission spectrum and their physical properties like electron temperatures and emission measures have been estimated. The electron temperatures from continuum spectra are found to be lower than the temperatures reported from radio recombination line (RRL) studies of these HII regions indicating the need for a filling factor even at this resolution. Also, the observed brightness at 240MHz is found to be higher than expected from the best fits suggesting the need for a multicomponent model for the region.", "tagged_title": "<property>Electron Temperatures</property> in <object>W51 Complex</object> from <property>High Resolution</property>, <property>Low Frequency</property> <modality>Radio</modality> Observations", "tagged_abstract": "<object>W51</object> is a giant <object><modality>radio</modality> complex</object> lying along the tangent to the <object>Sagitarius arm</object> at a distance of about 7kpc from <object>Sun</object>, with an extension of about 1deg in the sky. It is divided into three components A,B,C where <object>W51A</object> and <object>W51B</object> consist of many compact <object>HII regions </object> while <object>W51C</object> is a <object>supernova remnant</object>. We have made <dataset><modality>continuum radio</modality> observations</dataset> of these <object>HII regions</object> of the <object>W51</object> complex at 240,610,1060,1400 MHz using <instrument>GMRT</instrument> with lower resolution 20''x15'' at the lowest frequency. The observed <modality>spectra</modality> of the prominent <property>thermal subcomponents</property> of <object>W51</object> have been fitted to a free-free <object>emission spectrum</object> and their physical properties like <property>electron temperatures</property> and <property>emission measures</property> have been estimated. The <property>electron temperatures</property> from <modality>continuum spectra</modality> are found to be lower than the <property>temperatures</property> reported from <method>radio recombination line (RRL) studies</method> of these <object>HII regions</object> indicating the need for a filling factor even at this resolution. Also, the observed <property>brightness</property> at 240MHz is found to be higher than expected from the best fits suggesting the need for a <model>multicomponent model</model> for the region.", "tagged_phrases": {"property": ["Electron Temperatures", "High Resolution", "Low Frequency", "thermal subcomponents", "electron temperatures", "emission measures", "temperatures", "brightness"], "object": ["W51 Complex", "W51", "radio complex", "Sagitarius arm", "Sun", "W51A", "W51B", "HII regions", "W51C", "supernova remnant", "emission spectrum"], "modality": ["Radio", "radio", "continuum radio", "spectra", "continuum spectra"], "dataset": ["continuum radio observations"], "instrument": ["GMRT"], "method": ["radio recombination line (RRL) studies"], "model": ["multicomponent model"]}}
{"title": "Dynamical Study of A1689 from Wide-Field VLT/VIMOS Spectroscopy: Mass Profile, Concentration Parameter, and Velocity Anisotropy", "abstract": "We examine the dynamics structure of the rich cluster A1689, combining VLT/VIMOS spectroscopy with Subaru/Suprime-Cam imaging. The radial velocity distribution of $\\sim 500$ cluster members is bounded by a pair of clearly defined velocity caustics, with a maximum amplitude of $\\sim|4000|$ km/s at $\\simeq$ 300 h$^{-1}$ kpc, beyond which the amplitude steadily declines, approaching zero velocity at a limiting radius of $\\sim$ 2 h$^{-1}$ Mpc. We derive the 3D velocity anisotropy and galaxy number density profiles using a model-independent method to solve the Jeans equation, simultaneously incorporating the observed velocity dispersion profile, the galaxy counts from deep Subaru imaging, and our previously derived cluster mass profile from a joint lensing and X-ray analysis. The velocity anisotropy is found to be predominantly radial at large radius, becoming increasingly tangential towards the center, in accord with expectations. We also analyze the galaxy data independently of our previous analysis using two different methods: The first is based on a solution of the Jeans equation assuming an NFW form for the mass distribution, whereas in the second method the caustic amplitude is used to determine the escape velocity. The cluster virial mass derived by both of these dynamical methods is in good agreement with results from our earlier lensing and X-ray analysis. We also confirm the high NFW concentration parameter, with results from both methods combined to yield $c_{\\rm vir}>13$ (1$\\sigma$). The inferred virial radius is consistent with the limiting radius where the caustics approach zero velocity and where the counts of cluster members drop off, suggesting that infall onto A1689 is currently not significant.", "tagged_title": "Dynamical Study of <object>A1689</object> from <object>Wide-Field <instrument>VLT/VIMOS</instrument> <modality>Spectroscopy</modality></object>: <property>Mass Profile</property>, <property>Concentration Parameter</property>, and <property>Velocity Anisotropy</property>", "tagged_abstract": "We examine the dynamics structure of the rich <object>cluster A1689</object>, combining <modality><instrument>VLT/VIMOS</instrument> spectroscopy</modality> with <modality><instrument>Subaru/Suprime-Cam</instrument> imaging</modality>. The <property>radial velocity distribution</property> of $\\sim 500$ <object>cluster members</object> is bounded by a pair of clearly defined velocity caustics, with a maximum <property>amplitude</property> of $\\sim|4000|$ km/s at $\\simeq$ 300 h$^{-1}$ kpc, beyond which the <property>amplitude</property> steadily declines, approaching zero velocity at a limiting <property>radius</property> of $\\sim$ 2 h$^{-1}$ Mpc. We derive the <property>3D velocity anisotropy</property> and <property>galaxy number density</property> profiles using a model-independent method to solve the <method>Jeans equation</method>, simultaneously incorporating the observed <property>velocity dispersion</property> profile, the <property>galaxy counts</property> from deep <instrument>Subaru imaging</instrument>, and our previously derived <property>cluster mass</property> profile from a <modality>joint lensing</modality> and <modality>X-ray</modality> analysis. The <property>velocity anisotropy</property> is found to be predominantly <property>radial</property> at large <property>radius</property>, becoming increasingly tangential towards the center, in accord with expectations. We also analyze the <object>galaxy</object> data independently of our previous analysis using two different methods: The first is based on a solution of the <method>Jeans equation</method> assuming an <method>NFW form for the mass distribution</method>, whereas in the second method the <property>caustic amplitude</property> is used to determine the <property>escape velocity</property>. The <object>cluster</object> <property>virial mass</property> derived by both of these dynamical methods is in good agreement with results from our earlier <modality>lensing</modality> and <modality>X-ray</modality> analysis. We also confirm the high <property>NFW concentration parameter</property>, with results from both methods combined to yield $c_{\\rm vir}>13$ (1$\\sigma$). The inferred <property>virial radius</property> is consistent with the limiting <property>radius</property> where the <property>caustics</property> approach zero <property>velocity</property> and where the counts of <object>cluster</object> members drop off, suggesting that infall onto <object>A1689</object> is currently not significant.", "tagged_phrases": {"object": ["A1689", "Wide-Field VLT/VIMOS Spectroscopy", "cluster A1689", "cluster members", "galaxy", "cluster"], "instrument": ["VLT/VIMOS", "Subaru/Suprime-Cam", "Subaru imaging"], "modality": ["Spectroscopy", "VLT/VIMOS spectroscopy", "Subaru/Suprime-Cam imaging", "joint lensing", "X-ray", "lensing"], "property": ["Mass Profile", "Concentration Parameter", "Velocity Anisotropy", "radial velocity distribution", "amplitude", "radius", "3D velocity anisotropy", "galaxy number density", "velocity dispersion", "galaxy counts", "cluster mass", "velocity anisotropy", "radial", "caustic amplitude", "escape velocity", "virial mass", "NFW concentration parameter", "virial radius", "caustics", "velocity"], "method": ["Jeans equation", "NFW form for the mass distribution"]}}
{"title": "Systematic thermal reduction of neutronization in core-collapse supernovae", "abstract": "We investigate to what extent the temperature dependence of the nuclear symmetry energy can affect the neutronization of the stellar core prior to neutrino trapping during gravitational collapse. To this end, we implement a one-zone simulation to follow the collapse until beta equilibrium is reached and the lepton fraction remains constant. Since the strength of electron capture on the neutron-rich nuclei associated to the supernova scenario is still an open issue, we keep it as a free parameter. We find that the temperature dependence of the symmetry energy consistently yields a small reduction of deleptonization, which corresponds to a systematic effect on the shock wave energetics: the gain in dissociation energy of the shock has a small yet non-negligible value of about 0.4 foe (1 foe = 10^51 erg) and this result is almost independent from the strength of nuclear electron capture. The presence of such a systematic effect and its robustness under changes of the parameters of the one-zone model are significative enough to justify further investigations with detailed numerical simulations of supernova explosions.", "tagged_title": "Systematic thermal reduction of <property>neutronization</property> in <property>core-collapse</property> <object>supernovae</object>", "tagged_abstract": "We investigate to what extent the <property>temperature dependence</property> of the <object>nuclear symmetry energy</object> can affect the <property>neutronization</property> of the <object>stellar core</object> prior to <object>neutrino</object> trapping during <object>gravitational collapse</object>. To this end, we implement a <method>one-zone simulation</method> to follow the <property>collapse</property> until <property>beta equilibrium</property> is reached and the <object>lepton fraction</object> remains constant. Since the <property>strength</property> of <object><object>electron</object> capture</object> on the <property>neutron-rich</property> <object>nuclei</object> associated to the <object>supernova</object> scenario is still an open issue, we keep it as a free parameter. We find that the <property>temperature dependence</property> of the <object>symmetry energy</object> consistently yields a small reduction of <object>deleptonization</object>, which corresponds to a systematic effect on the <object>shock wave energetics</object>: the gain in <property>dissociation energy</property> of the shock has a small yet non-negligible value of about 0.4 foe (1 foe = 10^51 erg) and this result is almost independent from the <property> strength</property> of <object>nuclear <object>electron</object> capture</object>. The presence of such a systematic effect and its robustness under changes of the parameters of the <method>one-zone model</method> are significative enough to justify further investigations with detailed <task>numerical simulations</task> of <object>supernova explosions</object>.", "tagged_phrases": {"property": ["neutronization", "core-collapse", "temperature dependence", "collapse", "beta equilibrium", "strength", "neutron-rich", "dissociation energy"], "object": ["supernovae", "nuclear symmetry energy", "stellar core", "neutrino", "gravitational collapse", "lepton fraction", "electron capture", "electron", "nuclei", "supernova", "symmetry energy", "deleptonization", "shock wave energetics", "nuclear electron capture", "supernova explosions"], "method": ["one-zone simulation", "one-zone model"], "task": ["numerical simulations"]}}
{"title": "Hadrons As Kerr-Newman Black Holes", "abstract": "The scale invariance of the source-free Einstein field equations suggests that one might be able to model hadrons as \"strong gravity\" black holes, if one uses an appropriate rescaling of units or a revised gravitational coupling factor. The inner consistency of this hypothesis is tested by retrodicting a close approximation to the mass of the proton from an equation that relates the angular momentum and mass of a Kerr black hole. More accurate mass and radius values for the proton are then retrodicted using the geometrodynamics form of the full Kerr-Newman solution of the Einstein-Maxwell equations. The radius of an alpha particle is calculated as an additional retrodictive test. In a third retrodictive test of the \"strong gravity\" hypothesis, the subatomic particle mass spectrum in the 100 MeV to 7,000 MeV range is retrodicted to a first approximation using the Kerr solution of General Relativity. The particle masses appear to form a restricted set of quantized values of the Kerr solution: n^1/2 M, where values of n are a set of discrete integers and M is the revised Planck mass. The accuracy of the 27 retrodicted masses averages 98.4%. Finally, the new atomic scale gravitational coupling constant suggests a radical revision of the assumptions governing the Planck scale, and leads to a natural explanation for the fine structure constant.", "tagged_title": "<object>Hadrons</object> As <object>Kerr-Newman Black Holes</object>", "tagged_abstract": "The <property>scale invariance</property> of the source-free <model>Einstein field equations</model> suggests that one might be able to model <object>hadrons</object> as <property>\"strong gravity\"</property> <object>black holes</object>, if one uses an appropriate rescaling of units or a revised <object>gravitational coupling factor</object>. The inner consistency of this hypothesis is tested by <task>retrodicting</task> a close approximation to the <property>mass</property> of the <object>proton</object> from an equation that relates the <property>angular momentum</property> and <property>mass</property> of a <object>Kerr black hole</object>. More accurate <property>mass</property> and <property>radius</property> values for the <object>proton</object> are then retrodicted using the <method>geometrodynamics form</method> of the <method>full Kerr-Newman solution</method> of the <model>Einstein-Maxwell equations</model>. The <property>radius</property> of an <object>alpha particle</object> is calculated as an additional <task>retrodictive test</task>. In a third <task>retrodictive test</task> of the \"strong gravity\" hypothesis, the <modality>subatomic particle mass spectrum</modality> in the 100 MeV to 7,000 MeV range is <task>retrodicted</task> to a first approximation using the <method>Kerr solution of General Relativity</method>. The <object>particle masses</object> appear to form a restricted set of quantized values of the <method>Kerr solution</method>: n^1/2 M, where values of <property>n</property> are a set of discrete integers and <property>M</property> is the revised <property>Planck mass</property>. The accuracy of the 27 <object>retrodicted masses</object> averages 98.4%. Finally, the new atomic scale <object>gravitational coupling constant</object> suggests a radical revision of the assumptions governing the <object>Planck scale</object>, and leads to a natural explanation for the <object>fine structure constant</object>.", "tagged_phrases": {"object": ["Hadrons", "Kerr-Newman Black Holes", "hadrons", "black holes", "gravitational coupling factor", "proton", "Kerr black hole", "alpha particle", "particle masses", "retrodicted masses", "gravitational coupling constant", "Planck scale", "fine structure constant"], "property": ["scale invariance", "\"strong gravity\"", "mass", "angular momentum", "radius", "n", "M", "Planck mass"], "model": ["Einstein field equations", "Einstein-Maxwell equations"], "task": ["retrodicting", "retrodictive test", "retrodicted"], "method": ["geometrodynamics form", "full Kerr-Newman solution", "Kerr solution of General Relativity", "Kerr solution"], "modality": ["subatomic particle mass spectrum"]}}
{"title": "Large-Scale Magnetic-Field Generation by Randomly Forced Shearing Waves", "abstract": "A rigorous theory for the generation of a large-scale magnetic field by random non-helically forced motions of a conducting fluid combined with a linear shear is presented in the analytically tractable limit of low Rm and weak shear. The dynamo is kinematic and due to fluctuations in the net (volume-averaged) electromotive force. This is a minimal proof-of-concept quasilinear calculation aiming to put the shear dynamo, a new effect recently found in numerical experiments, on a firm theoretical footing. Numerically observed scalings of the wavenumber and growth rate of the fastest growing mode, previously not understood, are derived analytically. The simplicity of the model suggests that shear dynamo action may be a generic property of sheared magnetohydrodynamic turbulence.", "tagged_title": "<task>Large-Scale Magnetic-Field Generation</task> by <method>Randomly Forced Shearing Waves</method>", "tagged_abstract": "A rigorous theory for the <task>generation of a large-scale <object>magnetic field</object></task> by <method>random non-helically forced motions</method> of a <object>conducting fluid</object> combined with a <method>linear shear</method> is presented in the analytically tractable limit of low Rm and weak shear. The <property>dynamo</property> is <property>kinematic</property> and due to fluctuations in the net (volume-averaged) <object>electromotive force</object>. This is a minimal proof-of-concept quasilinear calculation aiming to put the <property>shear dynamo</property>, a new effect recently found in numerical experiments, on a firm theoretical footing. Numerically observed scalings of the <property>wavenumber</property> and <property>growth rate</property> of the fastest growing <object>mode</object>, previously not understood, are derived analytically. The simplicity of the model suggests that <property>shear dynamo action</property> may be a generic property of sheared <object>magnetohydrodynamic turbulence</object>.", "tagged_phrases": {"task": ["Large-Scale Magnetic-Field Generation", "generation of a large-scale magnetic field"], "method": ["Randomly Forced Shearing Waves", "random non-helically forced motions", "linear shear"], "object": ["magnetic field", "conducting fluid", "electromotive force", "mode", "magnetohydrodynamic turbulence"], "property": ["dynamo", "kinematic", "shear dynamo", "wavenumber", "growth rate", "shear dynamo action"]}}
{"title": "Sunyaev-Zel'dovich Effect Observations of the Bullet Cluster (1E 0657-56) with APEX-SZ", "abstract": "We present observations of the Sunyaev-Zel'dovich effect (SZE) in the Bullet cluster (1E 0657--56) using the APEX-SZ instrument at 150 GHz with a resolution of 1 arcmin. The main results are maps of the SZE in this massive, merging galaxy cluster. The cluster is detected with 23 sigma significance within the central 1 arcmin radius of the source position. The SZE map has a broadly similar morphology to that in existing X-ray maps of this system, and we find no evidence for significant contamination of the SZE emission by radio or IR sources. In order to make simple quantitative comparisons with cluster gas models derived from X-ray observations, we fit our data to an isothermal elliptical beta model, despite the inadequacy of such a model for this complex merging system. With an X-ray derived prior on the power-law index, beta = 1.04 +0.16 -0.10, we find a core radius r_c =142 +/- 18 arcsec, an axial ratio of 0.889 +/- 0.072, and a central temperature decrement of -771 +/- 71 micro-K_CMB, including a +/-5.5% flux calibration uncertainty. Combining the APEX-SZ map with a map of projected electron surface density from Chandra X-ray observations, we determine the mass-weighted temperature of the cluster gas to be T_mg=10.8 +/- 0.9 keV, significantly lower than some previously reported X-ray spectroscopic temperatures. Under the assumption of an isothermal cluster gas distribution in hydrostatic equilibrium, we compute the gas mass fraction for prolate and oblate spheroidal geometries and find it to be consistent with previous results from X-ray and weak lensing observations. This work is the first result from the APEX-SZ experiment, and represents the first reported scientific result from observations with a large array of multiplexed superconducting transition-edge sensor bolometers.", "tagged_title": "<object>Sunyaev-Zel'dovich Effect</object> Observations of the <object>Bullet Cluster (1E 0657-56)</object> with <instrument>APEX-SZ</instrument>", "tagged_abstract": "We present observations of the <object>Sunyaev-Zel'dovich effect (SZE)</object> in the <object>Bullet cluster (1E 0657--56) </object> using the <instrument>APEX-SZ</instrument> instrument at 150 GHz with a resolution of 1 arcmin. The main results are maps of the <object>SZE</object> in this massive, merging <object>galaxy cluster</object>. The <object>cluster</object> is detected with 23 sigma significance within the central 1 arcmin <property>radius</property> of the source position. The <object>SZE map</object> has a broadly similar morphology to that in existing <object><modality>X-ray</modality> maps</object> of this system, and we find no evidence for significant contamination of the <object>SZE emission</object> by <modality>radio</modality> or <modality>IR</modality> sources. In order to make simple quantitative comparisons with <model><object>cluster gas</object> models</model> derived from <dataset><modality>X-ray</modality> observations</dataset>, we fit our data to an <method>isothermal elliptical beta model</method>, despite the inadequacy of such a model for this complex merging system. With an <modality>X-ray</modality> derived prior on the <object>power-law index</object>, beta = 1.04 +0.16 -0.10, we find a core <property>radius</property> r_c =142 +/- 18 arcsec, an <property>axial ratio</property> of 0.889 +/- 0.072, and a central <property>temperature decrement</property> of -771 +/- 71 micro-K_CMB, including a +/-5.5% <property>flux calibration uncertainty</property>. Combining the <object><instrument>APEX-SZ</instrument> map </object> with a map of projected electron surface density from <dataset><instrument>Chandra<instrument> <modality>X-ray</modality> observations</dataset>, we determine the <property>mass-weighted</property> <property>temperature</property> of the <object>cluster gas</object> to be T_mg=10.8 +/- 0.9 keV, significantly lower than some previously reported <modality>X-ray spectroscopic</modality> temperatures. Under the assumption of an isothermal <object>cluster gas</object> distribution in hydrostatic equilibrium, we compute the <property>gas mass fraction</property> for <object>prolate</object> and <object>oblate spheroidal geometries</object> and find it to be consistent with previous results from <modality>X-ray</modality> and <modality>weak lensing</modality> observations. This work is the first result from the <instrument>APEX-SZ</instrument> experiment, and represents the first reported scientific result from observations with a large array of <instrument>multiplexed superconducting transition-edge sensor bolometers</instrument>.", "tagged_phrases": {"object": ["Sunyaev-Zel'dovich Effect", "Bullet Cluster (1E 0657-56)", "Sunyaev-Zel'dovich effect (SZE)", "Bullet cluster (1E 0657--56)", "SZE", "galaxy cluster", "cluster", "SZE map", "X-ray maps", "SZE emission", "cluster gas", "power-law index", "APEX-SZ map", "prolate", "oblate spheroidal geometries"], "instrument": ["APEX-SZ", "Chandra X-ray observations", "X-ray observations", "multiplexed superconducting transition-edge sensor bolometers"], "property": ["radius", "axial ratio", "temperature decrement", "flux calibration uncertainty", "mass-weighted", "temperature", "gas mass fraction"], "modality": ["X-ray", "radio", "IR", "X-ray spectroscopic", "weak lensing"], "model": ["cluster gas models"], "dataset": ["X-ray observations", "Chandra X-ray observations"], "method": ["isothermal elliptical beta model"]}}
{"title": "Natural Coordinate System in Curved Space-time", "abstract": "In this paper we establish a generally and globally valid coordinate system in curved space-time with the simultaneous hypersurface orthogonal to the time coordinate. The time coordinate can be preseted according to practical evolving process and keep synchronous with the evolution of the realistic world. In this coordinate system, it is convenient to express the physical laws and to calculate physical variables with clear geometrical meaning. We call it \"natural coordinate system\". The constructing method for the natural coordinate system is concretely provided, and its physical and geometrical meanings are discussed in detail. In NCS we make classical approximation of spinor equation to get Newtonian mechanics, and then make weak field approximation of Einstein's equation and low speed approximation of particles moving in the space-time. From the analysis and examples we find it is a nice coordinate system to describe the realistic curved space-time, and is helpful to understand the nature of space-time.", "tagged_title": "<model>Natural Coordinate System</model> in <object>Curved Space-time</object>", "tagged_abstract": "In this paper we establish a generally and globally valid <model>coordinate system</model> in <object>curved space-time</object> with the simultaneous <object>hypersurface orthogonal</object> to the <object>time coordinate</object>. The <object>time coordinate</object> can be preseted according to practical evolving process and keep synchronous with the evolution of the realistic world. In this <model>coordinate system</model>, it is convenient to express the physical laws and to calculate physical variables with clear <property>geometrical</property> meaning. We call it <model>\"natural coordinate system\"</model>. The constructing method for the <model>natural coordinate system</model> is concretely provided, and its <property>physcial</property> and <property>geometrical</property> meanings are discussed in detail. In <model>NCS</model> we make <method>classical approximation of spinor equation</method> to get <object>Newtonian mechanics</object>, and then make <method>weak field approximation of Einstein's equation</method> and <method>low speed approximation of particles</method> moving in the <object>space-time</object>. From the analysis and examples we find it is a nice <model>coordinate system</model> to describe the realistic <object>curved space-time</object>, and is helpful to understand the nature of <object>space-time</object>.", "tagged_phrases": {"model": ["Natural Coordinate System", "coordinate system", "\"natural coordinate system\"", "natural coordinate system", "NCS"], "object": ["Curved Space-time", "curved space-time", "hypersurface orthogonal", "time coordinate", "Newtonian mechanics", "space-time"], "property": ["geometrical", "physcial"], "method": ["classical approximation of spinor equation", "weak field approximation of Einstein's equation", "low speed approximation of particles"]}}
{"title": "2MTF I. The Tully-Fisher Relation in the 2MASS J, H and K Bands", "abstract": "The 2 Micron All-Sky Survey (2MASS) Tully-Fisher Survey (2MTF) aims to measure Tully-Fisher (TF) distances to all bright inclined spirals in the 2MASS Redshift Survey (2MRS). Essential to this project is a universal calibration of the TF relation in the 2MASS J (1.2 um), H (1.6 um) and K (2.2 um) bands. We present the first bias corrected or universal TF template in these bands. We find that the slope of the TF relation becomes steeper as the wavelength increases being close to L \\propto v^4 in K-band and L \\propto v^3.6 in J and H-bands. We also investigate the dependence on galaxy morphology showing that in all three bands the relation is steeper for later type spirals which also have a dimmer TF zeropoint than earlier type spirals. We correct the final relation to that for Sc galaxies. Finally we study the scatter from the TF relation fitting for a width dependent intrinsic scatter which is not found to vary significantly with wavelength.", "tagged_title": "2MTF I. <method>The Tully-Fisher Relation</method> in <object>the 2MASS J, H and K Bands</object>", "tagged_abstract": "<dataset>The 2 Micron All-Sky Survey (2MASS)</dataset> <dataset>Tully-Fisher Survey (2MTF)</dataset> aims to measure <property>Tully-Fisher (TF) distances</property> to all <object>bright inclined spirals</object> in <dataset>the 2MASS Redshift Survey (2MRS)</dataset>. Essential to this project is a <method>universal calibration</method> of the <method>TF relation</method> in <object>the 2MASS J (1.2 um), H (1.6 um) and K (2.2 um) bands</object>. We present the first <model>bias corrected or universal TF template</model> in these bands. We find that the slope of the <method>TF relation</method> becomes steeper as <property>the wavelength</property> increases being close to L \\propto v^4 in <object>K-band</object> and L \\propto v^3.6 in <object>J and H-bands</object>. We also investigate the dependence on <property>galaxy morphology</property> showing that in all three bands the relation is steeper for <object>later type spirals</object> which also have a dimmer <property>TF zeropoint</property> than <object>earlier type spirals</object>. We correct the final relation to that for <object>Sc galaxies</object>. Finally we study the scatter from the <method>TF relation</method> fitting for a width dependent intrinsic scatter which is not found to vary significantly with <object>wavelength</object>.", "tagged_phrases": {"method": ["The Tully-Fisher Relation", "universal calibration", "TF relation"], "object": ["the 2MASS J, H and K Bands", "bright inclined spirals", "the 2MASS J (1.2 um), H (1.6 um) and K (2.2 um) bands", "K-band", "J and H-bands", "later type spirals", "earlier type spirals", "Sc galaxies", "wavelength"], "dataset": ["The 2 Micron All-Sky Survey (2MASS)", "Tully-Fisher Survey (2MTF)", "the 2MASS Redshift Survey (2MRS)"], "property": ["Tully-Fisher (TF) distances", "the wavelength", "galaxy morphology", "TF zeropoint"], "model": ["bias corrected or universal TF template"]}}
{"title": "The S1 Shell and Interstellar Magnetic Field and Gas near the Heliosphere", "abstract": "Many studies of the Loop I magnetic superbubble place the Sun at the edges of the bubble. One recent study models the polarized radio continuum of Loop I as two magnetic shells with the Sun embedded in the rim of the 'S1' shell. If the Sun is in such a shell, it should be apparent in both the local interstellar magnetic field and the distribution of nearby interstellar material. The properties of these subshells are compared to optical polarization data that trace the nearby interstellar magnetic field (ISMF), and the distribution of interstellar FeII and CaII within about 55 pc of the Sun. The result is that a model of Loop I as composed of two magnetic subshells is a viable description of the distribution of nearby low density ISM. Column densities of the recombinant ion CaII are found to increase with the strength of the interstellar radiation field, rather than with star distance or total pathlength through the two magnetic subshells. As found earlier, the symmetry of the dipole moment of the cosmic microwave background corresponds to the symmetries of the heliosphere and local ISMF (to within 10 degrees).", "tagged_title": "The <object>S1 Shell</object> and <object>Interstellar Magnetic Field</object> and Gas near <object>the Heliosphere</object>", "tagged_abstract": "Many studies of the <object>Loop I magnetic superbubble</object> place <object>the Sun</object> at the edges of the bubble. One recent study models <object>the polarized radio continuum</object> of <object>Loop I</object> as two <object>magnetic shells</object> with <object>the Sun</object> embedded in the rim of <object>the 'S1' shell</object>. If <object>the Sun</object> is in such a shell, it should be apparent in both <object>the local interstellar magnetic field</object> and the distribution of nearby <object>interstellar material</object>. The properties of these subshells are compared to <modality>optical polarization data</modality> that trace the nearby <object>interstellar magnetic field (ISMF)</object>, and the distribution of <object>interstellar FeII and CaII</object> within about 55 pc of <object>the Sun</object>. The result is that a model of <object>Loop I</object> as composed of two <object>magnetic subshells</object> is a viable description of the distribution of nearby <object>low density ISM</object>. <property>Column densities</property> of <object>the recombinant ion CaII</object> are found to increase with the strength of <object>the interstellar radiation field</object>, rather than with <property>star distance</property> or <property>total pathlength</property> through the two <object>magnetic subshells</object>. As found earlier, the symmetry of <property>the dipole moment</property> of <object>the cosmic microwave background</object> corresponds to the symmetries of <object>the heliosphere</object> and <object>local ISMF</object> (to within 10 degrees).", "tagged_phrases": {"object": ["S1 Shell", "Interstellar Magnetic Field", "the Heliosphere", "Loop I magnetic superbubble", "the Sun", "the polarized radio continuum", "Loop I", "magnetic shells", "the 'S1' shell", "the local interstellar magnetic field", "interstellar material", "interstellar magnetic field (ISMF)", "interstellar FeII and CaII", "magnetic subshells", "low density ISM", "the recombinant ion CaII", "the interstellar radiation field", "the cosmic microwave background", "the heliosphere", "local ISMF"], "modality": ["optical polarization data"], "property": ["Column densities", "star distance", "total pathlength", "the dipole moment"]}}
{"title": "The growth of supermassive black holes in pseudo-bulges, classical bulges and elliptical galaxies", "abstract": "Using results from structural analysis of a sample of nearly 1000 local galaxies from the Sloan Digital Sky Survey, we estimate how the mass in central black holes is distributed amongst elliptical galaxies, classical bulges and pseudo-bulges, and investigate the relation between their stellar masses and central stellar velocity dispersion sigma. Assuming a single relation between elliptical galaxy/bulge mass, M_Bulge, and central black hole mass, M_BH, we find that 55^{+8}_{-4} per cent of the mass in black holes in the local universe is in the centres of elliptical galaxies, 41^{+4}_{-2} per cent in classical bulges and 4^{+0.9}_{-0.4} per cent in pseudo-bulges. We find that ellipticals, classical bulges and pseudo-bulges follow different relations between their stellar masses and sigma, and the most significant offset occurs for pseudo-bulges in barred galaxies. This structural dissimilarity leads to discrepant black hole masses if single M_BH-M_Bulge and M_BH-sigma relations are used. Adopting relations from the literature, we find that the M_BH-sigma relation yields an estimate of the total mass density in black holes that is roughly 55 per cent larger than if the M_BH-M_Bulge relation is used.", "tagged_title": "The growth of <object>supermassive black holes</object> in <object>pseudo-bulges</object>, <object>classical bulges</object> and <object>elliptical galaxies</object>", "tagged_abstract": "Using results from <method>structural analysis</method> of a sample of nearly 1000 <object>local galaxies</object> from the <dataset>Sloan Digital Sky Survey</dataset>, we estimate how the <property>mass</property> in <object>central black holes</object> is distributed amongst <object>elliptical galaxies</object>, <object>classical bulges</object> and <object>pseudo-bulges</object>, and investigate the relation between their <property>stellar masses</property> and <property>central stellar velocity dispersion sigma</property>. Assuming a single relation between <property>elliptical galaxy/bulge mass</property>, M_Bulge, and <property>central black hole mass</property>, M_BH, we find that 55^{+8}_{-4} per cent of the <property>mass</property> in <object>black holes</object> in the <object>local universe</object> is in the centres of <object>elliptical galaxies</object>, 41^{+4}_{-2} per cent in <object>classical bulges</object> and 4^{+0.9}_{-0.4} per cent in <object>pseudo-bulges</object>. We find that <object>ellipticals</object>, <object>classical bulges</object> and <object>pseudo-bulges</object> follow different relations between their <property>stellar masses</property> and <property>sigma</property>, and the most significant offset occurs for <object>pseudo-bulges</object> in <object>barred galaxies</object>. This structural dissimilarity leads to discrepant <property>black hole masses</property> if single M_BH-M_Bulge and M_BH-sigma relations are used. Adopting relations from the literature, we find that the M_BH-sigma relation yields an estimate of the <property>total mass density</property> in <object>black holes</object> that is roughly 55 per cent larger than if the M_BH-M_Bulge relation is used.", "tagged_phrases": {"object": ["supermassive black holes", "pseudo-bulges", "classical bulges", "elliptical galaxies", "local galaxies", "central black holes", "black holes", "local universe", "ellipticals", "barred galaxies"], "method": ["structural analysis"], "dataset": ["Sloan Digital Sky Survey"], "property": ["mass", "stellar masses", "central stellar velocity dispersion sigma", "elliptical galaxy/bulge mass", "central black hole mass", "sigma", "black hole masses", "total mass density"]}}
{"title": "Characteristic Scales of Initial Density and Velocity Fields", "abstract": "For the initial fields of the density contrast and peculiar velocity, we theoretically calculate the differential and integral length scales, i.e., statistical measures that respectively characterize the small- and large-scale fluctuations of a random field. These length scales and the associated mass scales explain the length and mass scales observed for (1) halos of young galaxies at z > 5, (2) halos of galaxies at z = 0, and (3) the largest structures in the galaxy distribution at z = 0. We thereby discuss that such observed scales are fossil imprints of the characteristic scales of the initial fields.", "tagged_title": "<property>Characteristic Scales</property> of <object>Initial Density and Velocity Fields</object>", "tagged_abstract": "For the <object>initial fields</object> of the <object>density contrast</object> and <object>peculiar velocity</object>, we theoretically calculate the <property>differential and integral length scales</property>, i.e., statistical measures that respectively characterize the small- and large-scale fluctuations of a <object>random field</object>. These <property>length scales</property> and the associated <property>mass scales</property> explain the <property>length and mass scales</property> observed for (1) <object>halos of young galaxies</object> at z > 5, (2) <object>halos of galaxies</object> at z = 0, and (3) the largest structures in the <object>galaxy distribution</object> at z = 0. We thereby discuss that such observed scales are fossil imprints of the <property>characteristic scales</property> of the <property>initial fields</property>.", "tagged_phrases": {"property": ["Characteristic Scales", "differential and integral length scales", "length scales", "mass scales", "length and mass scales", "characteristic scales", "initial fields"], "object": ["Initial Density and Velocity Fields", "initial fields", "density contrast", "peculiar velocity", "random field", "halos of young galaxies", "halos of galaxies", "galaxy distribution"]}}
{"title": "Gravitino Dark Matter and the Flavour Structure of R-violating Operators", "abstract": "We study gravitino dark matter and slow gravitino decays within the framework of R-violating supersymmetry, with particular emphasis on the flavour dependence of the branching ratios and the allowed R-violating couplings. The dominant decay modes and final state products turn out to be very sensitive to the R-violating hierarchies. Mixing effects can be crucial in correctly deriving the relative magnitude of the various contributions, particularly for heavy flavours with phase space suppression. The study of the strength of different decay rates for the gravitino is also correlated to collider signatures expected from decays of the Next-to-Lightest Supersymmetric Particle (NLSP) and to single superparticle production.", "tagged_title": "<object>Gravitino Dark Matter</object> and the Flavour Structure of <object>R-violating Operators</object>", "tagged_abstract": "We study <object>gravitino dark matter</object> and slow <object>gravitino decays</object> within the framework of <object>R-violating supersymmetry</object>, with particular emphasis on the <property>flavour dependence</property> of the branching ratios and the allowed <object>R-violating couplings</object>. The dominant <property>decay modes</property> and <property>final state products</property> turn out to be very sensitive to the R-violating hierarchies. <method>Mixing effects</method> can be crucial in correctly deriving the relative <property>magnitude</property> of the various contributions, particularly for heavy flavours with <property>phase space suppression</property>. The study of the <property>strength of different decay rates</property> for the <object>gravitino</object> is also correlated to collider signatures expected from decays of the <object>Next-to-Lightest Supersymmetric Particle</object> (NLSP) and to single <object>superparticle</object> production.", "tagged_phrases": {"object": ["Gravitino Dark Matter", "R-violating Operators", "gravitino dark matter", "gravitino decays", "R-violating supersymmetry", "R-violating couplings", "gravitino", "Next-to-Lightest Supersymmetric Particle", "superparticle"], "property": ["flavour dependence", "decay modes", "final state products", "magnitude", "phase space suppression", "strength of different decay rates"], "method": ["Mixing effects"]}}
{"title": "Dark Matter Caustics in Galaxy Clusters", "abstract": "We interpret the recent gravitational lensing observations of Jee et al. \\cite{Jee} as first evidence for a {\\it caustic} ring of dark matter in a galaxy cluster. A caustic ring unavoidably forms when a cold collisionless flow falls with net overall rotation in and out of a gravitational potential well. Evidence for caustic rings of dark matter was previously found in the Milky Way and other isolated spiral galaxies. We argue that galaxy clusters have at least one and possibly two or three caustic rings. We calculate the column density profile of a caustic ring in a cluster and show that it is consistent with the observations of Jee et al.", "tagged_title": "<object>Dark Matter Caustics</object> in <object>Galaxy Clusters</object>", "tagged_abstract": "We interpret the recent <modality><object>gravitational lensing</object> observations</modality> of Jee et al. \\cite{Jee} as first evidence for a <object>{\\it caustic} ring</object> of <object>dark matter</object> in a <object>galaxy cluster</object>. A <object>caustic ring</object> unavoidably forms when a <property>cold</property> <property>collisionless</property> <object>flow</object> falls with <property>net overall rotation</property> in and out of a <object>gravitational potential well</object>. Evidence for <object>caustic rings</object> of <object>dark matter</object> was previously found in the <object>Milky Way</object> and other <property>isolated</property> <property>spiral</property> <object>galaxies</object>. We argue that <object>galaxy clusters</object> have at least one and possibly two or three <object>caustic rings</object>. We <task>calculate the <property>column density profile</property></task> of a <object>caustic ring</object> in a <object>cluster</object> and <task>show that it is consistent with the observations of</task> Jee et al.", "tagged_phrases": {"object": ["Dark Matter Caustics", "Galaxy Clusters", "gravitational lensing", "caustic ring", "dark matter", "galaxy cluster", "flow", "gravitational potential well", "caustic rings", "Milky Way", "galaxies", "galaxy clusters", "cluster"], "modality": ["gravitational lensing observations"], "property": ["cold", "collisionless", "net overall rotation", "isolated", "spiral", "column density profile"], "task": ["calculate the column density profile", "show that it is consistent with the observations of"]}}
{"title": "Dark matter in elliptical galaxies: II. Estimating the mass within the virial radius", "abstract": "Elliptical galaxies are modelled with a a 4-component model: Sersic stars, LCDM dark matter (DM), hot gas and central black hole. DM is negligible in the inner regions, which are dominated by stars and the central black hole. This prevents any kinematical estimate (using a Jeans analysis) of the inner slope of the DM density profile. The gas fraction rises, but the baryon fraction decreases with radius, at least out to 10 effective radii (R_e). Even with line-of-sight velocity dispersion (VD) measurements at 4 to 6 R_e with 20 km/s accuracy and perfectly known velocity anisotropy, the total mass within the virial radius (r_v) is uncertain by a factor over 3. The DM distributions found in LCDM simulations are consistent with the stellar VD profiles, but appear inconsistent with the low VDs measured by Romanowsky et al. (2003) of planetary nebulae between 2 and 5 R_e, which imply such low M/Ls that the baryon fraction within r_v must be greater than the universal value. Replacing the NFW DM model by the new model of Navarro et al. (2004) decreases slightly the VD at a given radius. So, given the observed VD measured at 5 R_e, the inferred M/L within r_v is 40% larger than predicted with the NFW model. Folding in the slight (strong) radial anisotropy found in LCDM (merger) simulations, which is well modelled (much better than with the Osipkov-Merritt formula) with beta(r) = 1/2 r/(r+a), the inferred M/L within r_v is another 1.6 (2.4) times higher than for the isotropic NFW model. Thus, the DM model and radial anisotropy can partly explain the low PN VDs, but not in full. In an appendix, single integral expressions are derived for the VDs in terms of the tracer density and total mass profiles, for 3 anisotropic models: radial, Osipkov-Merritt, and the model above, for general radial profiles of luminosity density and mass.", "tagged_title": "<object>Dark matter</object> in <object>elliptical galaxies</object>: II. <task>Estimating the <property>mass</property> within the <property>virial radius</property></task>", "tagged_abstract": "<object>Elliptical galaxies</object> are <task>modelled</task> with a <model><property>4-component</property> model</model>: <object>Sersic stars</object>, <model>LCDM</model> <object>dark matter</object> (DM), <property>hot</property> <object>gas</object> and <property>central</property> <object>black hole</object>. DM is negligible in the <object>inner regions</object>, which are dominated by <object>stars</object> and the <property>central</property> <object>black hole</object>. This prevents any kinematical estimate (using a <method>Jeans analysis</method>) of the <property>inner slope</property> of the <object>DM density profile</object>. The <property>gas fraction</property> rises, but the <property>baryon fraction</property> decreases with <property>radius</property>, at least out to 10 <property>effective radii</property> (R_e). Even with <property>line-of-sight velocity dispersion</property> (VD) measurements at 4 to 6 R_e with 20 km/s accuracy and perfectly known <property>velocity anisotropy</property>, the total <property>mass</property> within the <property>virial radius</property> (r_v) is uncertain by a factor over 3. The DM distributions found in <method><model>LCDM</model> simulations</method> are consistent with the <modality>stellar VD profiles</modality>, but appear inconsistent with the low VDs measured by Romanowsky et al. (2003) of <object>planetary nebulae</object> between 2 and 5 R_e, which imply such low M/Ls that the <property>baryon fraction</property> within r_v must be greater than the universal value. Replacing the <model>NFW DM model</model> by the new <model>model of Navarro et al. (2004)</model> decreases slightly the VD at a given <property>radius</property>. So, given the observed VD measured at 5 R_e, the inferred M/L within r_v is 40% larger than predicted with the <model>NFW model</model>. Folding in the slight (strong) <property>radial anisotropy</property> found in <method><model>LCDM</model> (merger) simulations</method>, which is well modelled (much better than with the <model>Osipkov-Merritt formula</model>) with beta(r) = 1/2 r/(r+a), the inferred M/L within r_v is another 1.6 (2.4) times higher than for the <model>isotropic NFW model</model>. Thus, the <model>DM model</model> and <property>radial anisotropy</property> can partly explain the low PN VDs, but not in full. In an appendix, <task><method>single integral expressions</method> are derived</task> for the VDs in terms of the <property>tracer density</property> and <property>total mass</property> profiles, for 3 <model>anisotropic models</model>: <model>radial</model>, <model>Osipkov-Merritt</model>, and the model above, for general <property>radial profiles</property> of <property>luminosity</property> <property>density</property> and <property>mass</property>.", "tagged_phrases": {"object": ["Dark matter", "elliptical galaxies", "Elliptical galaxies", "Sersic stars", "dark matter", "gas", "black hole", "inner regions", "stars", "DM density profile", "planetary nebulae"], "task": ["Estimating the mass within the virial radius", "modelled", "single integral expressions are derived"], "property": ["mass", "virial radius", "4-component", "hot", "central", "inner slope", "gas fraction", "baryon fraction", "radius", "effective radii", "line-of-sight velocity dispersion", "velocity anisotropy", "radial anisotropy", "tracer density", "total mass", "radial profiles", "luminosity", "density"], "model": ["4-component model", "LCDM", "NFW DM model", "model of Navarro et al. (2004)", "NFW model", "Osipkov-Merritt formula", "isotropic NFW model", "DM model", "anisotropic models", "radial", "Osipkov-Merritt"], "method": ["Jeans analysis", "LCDM simulations", "LCDM (merger) simulations", "single integral expressions"], "modality": ["stellar VD profiles"]}}
{"title": "On the appearance of hyperons in neutron stars", "abstract": "By employing a recently constructed hyperon-nucleon potential the equation of state of \\beta-equilibrated and charge neutral nucleonic matter is calculated. The hyperon-nucleon potential is a low-momentum potential which is obtained within a renormalization group framework. Based on the Hartree-Fock approximation at zero temperature the densities at which hyperons appear in neutron stars are estimated. For several different bare hyperon-nucleon potentials and a wide range of nuclear matter parameters it is found that hyperons in neutron stars are always present. These findings have profound consequences for the mass and radius of neutron stars.", "tagged_title": "On the appearance of <object>hyperons</object> in <object>neutron stars</object>", "tagged_abstract": "By employing a recently constructed <model>hyperon-nucleon potential</model> the <property>equation of state</property> of <object>\\beta-equilibrated and charge neutral nucleonic matter</object> is calculated. The <model>hyperon-nucleon potential</model> is a low-<property>momentum</property> potential which is obtained within a <model>renormalization group</model> framework. Based on the <model>Hartree-Fock approximation</model> at zero <property>temperature</property> <task>the <property>densities</property> at which <object>hyperons</object> appear in <object>neutron stars</object> are estimated</task>. For several different <model>bare hyperon-nucleon potentials</model> and a wide range of nuclear matter parameters it is found that <object>hyperons</object> in <object>neutron stars</object> are always present. These findings have profound consequences for the <property>mass</property> and <property>radius</property> of <object>neutron stars</object>.", "tagged_phrases": {"object": ["hyperons", "neutron stars", "\\beta-equilibrated and charge neutral nucleonic matter"], "model": ["hyperon-nucleon potential", "renormalization group", "Hartree-Fock approximation", "bare hyperon-nucleon potentials"], "property": ["equation of state", "momentum", "temperature", "densities", "mass", "radius"], "task": ["the densities at which hyperons appear in neutron stars are estimated"]}}
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