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The plugin framework allows for application-specific backups and is used by Amanda Enterprise to support applications such as Oracle database, Samba network share, NDMP, etc.

Amanda Enterprise also supports image-level backup of live virtual machine running on VMware infrastructure.

Pathology is the study of the causes and effects of disease or injury.

The word pathology also refers to the study of disease in general, incorporating a wide range of biology research fields and medical practices.

A physician practicing pathology is called a pathologist.

As a field of general inquiry and research, pathology addresses components of disease: cause, mechanisms of development (pathogenesis), structural alterations of cells (morphologic changes), and the consequences of changes (clinical manifestations).

The medical practices of the Romans and those of the Byzantines continued from these Greek roots, but, as with many areas of scientific inquiry, growth in understanding of medicine stagnated some after the Classical Era, but continued to slowly develop throughout numerous cultures.

Notably, many advances were made in the medieval era of Islam (see Medicine in medieval Islam), during which numerous texts of complex pathologies were developed, also based on the Greek tradition.

Even so, growth in complex understanding of disease mostly languished until knowledge and experimentation again began to proliferate in the Renaissance, Enlightenment, and Baroque eras, following the resurgence of the empirical method at new centers of scholarship.

By the 17th century, the study of rudimentary microscopy was underway and examination of tissues had led British Royal Society member Robert Hooke to coin the word "cell", setting the stage for later germ theory.

Modern pathology began to develop as a distinct field of inquiry during the 19th Century through natural philosophers and physicians that studied disease and the informal study of what they termed “pathological anatomy” or “morbid anatomy”.

However, pathology as a formal area of specialty was not fully developed until the late 19th and early 20th centuries, with the advent of detailed study of microbiology.

With the new understanding of causative agents, physicians began to compare the characteristics of one germ's symptoms as they developed within an affected individual to another germ's characteristics and symptoms.

This approach led to the foundational understanding that diseases are able to replicate themselves, and that they can have many profound and varied effects on the human host.

To determine causes of diseases, medical experts used the most common and widely accepted assumptions or symptoms of their times, a general principal of approach that persists into modern medicine.

Modern medicine was particularly advanced by further developments of the microscope to analyze tissues, to which Rudolf Virchow gave a significant contribution, leading to a slew of research developments.

Biomedical research into disease incorporates the work of a vast variety of life science specialists, whereas, in most parts of the world, to be licensed to practice pathology as a medical specialty, one has to complete medical school and secure a license to practice medicine.

Structurally, the study of disease is divided into many different fields that study or diagnose markers for disease using methods and technologies particular to specific scales, organs, and tissue types.

Anatomical pathology is itself divided into subfields, the main divisions being surgical pathology, cytopathology, and forensic pathology.

Anatomical pathology is one of two main divisions of the medical practice of pathology, the other being clinical pathology, the diagnosis of disease through the laboratory analysis of bodily fluids and tissues.

The completion of this fellowship allows one to take a subspecialty board examination, and becomes a board certified dermatopathologist.

Dermatologists are able to recognize most skin diseases based on their appearances, anatomic distributions, and behavior.

Sometimes, however, those criteria do not lead to a conclusive diagnosis, and a skin biopsy is taken to be examined under the microscope using usual histological tests.

In some cases, additional specialized testing needs to be performed on biopsies, including immunofluorescence, immunohistochemistry, electron microscopy, flow cytometry, and molecular-pathologic analysis.

One of the greatest challenges of dermatopathology is its scope.

More than 1500 different disorders of the skin exist, including cutaneous eruptions ("rashes") and neoplasms.

An autopsy is typically performed by a coroner or medical examiner, often during criminal investigations; in this role, coroners and medical examiners are also frequently asked to confirm the identity of a corpse.

The requirements for becoming a licensed practitioner of forensic pathology varies from country to country (and even within a given nation) but typically a minimal requirement is a medical doctorate with a specialty in general or anatomical pathology with subsequent study in forensic medicine.

Specifically, in clinical medicine, histopathology refers to the examination of a biopsy or surgical specimen by a pathologist, after the specimen has been processed and histological sections have been placed onto glass slides.

This contrasts with the methods of cytopathology, which uses free cells or tissue fragments.

Histopathological examination of tissues starts with surgery, biopsy, or autopsy.

The tissue is removed from the body of an organism and then placed in a fixative that stabilizes the tissues to prevent decay.

The most common fixative is formalin, although frozen section fixing is also common.

To see the tissue under a microscope, the sections are stained with one or more pigments.

The aim of staining is to reveal cellular components; counterstains are used to provide contrast.

Histochemistry refers to the science of using chemical reactions between laboratory chemicals and components within tissue.

The histological slides are then interpreted diagnostically and the resulting pathology report describes the histological findings and the opinion of the pathologist.

In the case of cancer, this represents the tissue diagnosis required for most treatment protocols.

Neuropathology is a subspecialty of anatomic pathology, neurology, and neurosurgery.

In many English-speaking countries, neuropathology is considered a subfield of anatomical pathology.

A physician who specializes in neuropathology, usually by completing a fellowship after a residency in anatomical or general pathology, is called a neuropathologist.

In day-to-day clinical practice, a neuropathologist is a consultant for other physicians.

If a disease of the nervous system is suspected, and the diagnosis cannot be made by less invasive methods, a biopsy of nervous tissue is taken from the brain or spinal cord to aid in diagnosis.

Biopsy is usually requested after a mass is detected by medical imaging.

Epidermal nerve fiber density testing (ENFD) is a more recently developed neuropathology test in which a punch skin biopsy is taken to identify small fiber neuropathies by analyzing the nerve fibers of the skin.

This test is becoming available in select labs as well as many universities; it replaces the traditional nerve biopsy test as less invasive.

Diagnostic specimens are often obtained via bronchoscopic transbronchial biopsy, CT-guided percutaneous biopsy, or video-assisted thoracic surgery.

These tests can be necessary to diagnose between infection, inflammation, or fibrotic conditions.

In a medical setting, renal pathologists work closely with nephrologists and transplant surgeons, who typically obtain diagnostic specimens via percutaneous renal biopsy.

The renal pathologist must synthesize findings from traditional microscope histology, electron microscopy, and immunofluorescence to obtain a definitive diagnosis.

Surgical pathology involves the gross and microscopic examination of surgical specimens, as well as biopsies submitted by surgeons and non-surgeons such as general internists, medical subspecialists, dermatologists, and interventional radiologists.

Often an excised tissue sample is the best and most definitive evidence of disease (or lack thereof) in cases where tissue is surgically removed from a patient.

These determinations are usually accomplished by a combination of gross (i.e., macroscopic) and histologic (i.e., microscopic) examination of the tissue, and may involve evaluations of molecular properties of the tissue by immunohistochemistry or other laboratory tests.

There are two major types of specimens submitted for surgical pathology analysis: biopsies and surgical resections.

A biopsy is a small piece of tissue removed primarily for surgical pathology analysis, most often in order to render a definitive diagnosis.

Types of biopsies include core biopsies, which are obtained through the use of large-bore needles, sometimes under the guidance of radiological techniques such as ultrasound, CT scan, or magnetic resonance imaging.

Incisional biopsies are obtained through diagnostic surgical procedures that remove part of a suspicious lesion, whereas excisional biopsies remove the entire lesion, and are similar to therapeutic surgical resections.

Excisional biopsies of skin lesions and gastrointestinal polyps are very common.

The pathologist's interpretation of a biopsy is critical to establishing the diagnosis of a benign or malignant tumor, and can differentiate between different types and grades of cancer, as well as determining the activity of specific molecular pathways in the tumor.

Surgical resection specimens are obtained by the therapeutic surgical removal of an entire diseased area or organ (and occasionally multiple organs).

Clinical pathologists work in close collaboration with medical technologists, hospital administrations, and referring physicians.

Clinical pathologists learn to administer a number of visual and microscopic tests and an especially large variety of tests of the biophysical properties of tissue samples involving automated analysers and cultures.

Sometimes the general term "laboratory medicine specialist" is used to refer to those working in clinical pathology, including medical doctors, Ph.D.s and doctors of pharmacology.

Immunopathology, the study of an organism's immune response to infection, is sometimes considered to fall within the domain of clinical pathology.

The term hematopoietic system refers to tissues and organs that produce and/or primarily host hematopoietic cells and includes bone marrow, the lymph nodes, thymus, spleen, and other lymphoid tissues.

In the United States, hematopathology is a board certified subspecialty (licensed under the American Board of Pathology) practiced by those physicians who have completed a general pathology residency (anatomic, clinical, or combined) and an additional year of fellowship training in hematology.

The hematopathologist reviews biopsies of lymph nodes, bone marrows and other tissues involved by an infiltrate of cells of the hematopoietic system.

In addition, the hematopathologist may be in charge of flow cytometric and/or molecular hematopathology studies.

The crossover between molecular pathology and epidemiology is represented by a related field "molecular pathological epidemiology".

Molecular pathology is commonly used in diagnosis of cancer and infectious diseases.

Molecular Pathology is primarily used to detect cancers such as melanoma, brainstem glioma, brain tumors as well as many other types of cancer and infectious diseases.

Techniques are numerous but include quantitative polymerase chain reaction (qPCR), multiplex PCR, DNA microarray, in situ hybridization, DNA sequencing, antibody-based immunofluorescence tissue assays, molecular profiling of pathogens, and analysis of bacterial genes for antimicrobial resistance.

Techniques used are based on analyzing samples of DNA and RNA.

Pathology is widely used for gene therapy and disease diagnosis.

Oral Pathologists must complete three years of post doctoral training in an accredited program and subsequently obtain diplomate status from the American Board of Oral and Maxillofacial Pathology.

The specialty focuses on the diagnosis, clinical management and investigation of diseases that affect the oral cavity and surrounding maxillofacial structures including but not limited to odontogenic, infectious, epithelial, salivary gland, bone and soft tissue pathologies.

Training may be within two primary specialties, as recognized by the American Board of Pathology: anatomical pathology and clinical Pathology, each of which requires separate board certification.

The American Osteopathic Board of Pathology also recognizes four primary specialties: anatomic pathology, dermatopathology, forensic pathology, and laboratory medicine.

Pathologists may pursue specialised fellowship training within one or more subspecialties of either anatomical or clinical pathology.

Some of these subspecialties permit additional board certification, while others do not.

In the United Kingdom, pathologists are physicians licensed by the UK General Medical Council.

The training to become a pathologist is under the oversight of the Royal College of Pathologists.

After four to six years of undergraduate medical study, trainees proceed to a two-year foundation program.

Full-time training in histopathology currently lasts between five and five and a half years and includes specialist training in surgical pathology, cytopathology, and autopsy pathology.

It is also possible to take a Royal College of Pathologists diploma in forensic pathology, dermatopathology, or cytopathology, recognising additional specialist training and expertise and to get specialist accreditation in forensic pathology, pediatric pathology, and neuropathology.

All postgraduate medical training and education in the UK is overseen by the General Medical Council.

Residency in anatomical pathology is open to physicians only, while clinical pathology is open to both physicians and pharmacists.

At the end of the second year of clinical pathology residency, residents can choose between general clinical pathology and a specialization in one of the disciplines, but they can not practice anatomical pathology, nor can anatomical pathology residents practice clinical pathology.

As a significant portion of all general pathology practice is concerned with cancer, the practice of oncology makes extensive use of both anatomical and clinical pathology in diagnosis and treatment.

In particular, biopsy, resection, and blood tests are all examples of pathology work that is essential for the diagnoses of many kinds of cancer and for the staging of cancerous masses.

In a similar fashion, the tissue and blood analysis techniques of general pathology are of central significance to the investigation of serious infectious disease and as such inform significantly upon the fields of epidemiology, etiology, immunology, and parasitology.

General pathology methods are of great importance to biomedical research into disease, wherein they are sometimes referred to as "experimental" or "investigative" pathology.

Medical imaging is the generating of visual representations of the interior of a body for clinical analysis and medical intervention.

Medical imaging reveals details of internal physiology that help medical professionals plan appropriate treatments for tissue infection and trauma.

Medical imaging is also central in supplying the biometric data necessary to establish baseline features of anatomy and physiology so as to increase the accuracy with which early or fine-detail abnormalities are detected.

These diagnostic techniques are often performed in combination with general pathology procedures and are themselves often essential to developing new understanding of the pathogenesis of a given disease and tracking the progress of disease in specific medical cases.

For this reason, as well as their roles as livestock and companion animals, mammals generally have the largest body of research in veterinary pathology.

Animal testing remains a controversial practice, even in cases where it is used to research treatment for human disease.

Damage caused by insects, mites, vertebrate, and other small herbivores is not considered a part of the domain of plant pathology.

The field is connected to plant disease epidemiology and especially concerned with the horticulture of species that are of high importance to the human diet or other human utility.

In gamma-ray astronomy, gamma-ray bursts (GRBs) are immensely energetic explosions that have been observed in distant galaxies.

They are the most energetic and luminous electromagnetic events since the Big Bang.

Bursts can last from ten milliseconds to several hours.

After an initial flash of gamma rays, a longer-lived "afterglow" is usually emitted at longer wavelengths (X-ray, ultraviolet, optical, infrared, microwave and radio).

The intense radiation of most observed GRBs is thought to be released during a supernova or superluminous supernova as a high-mass star implodes to form a neutron star or a black hole.

A subclass of GRBs (the "short" bursts) appear to originate from the merger of binary neutron stars.

The cause of the precursor burst observed in some of these short events may be the development of a resonance between the crust and core of such stars as a result of the massive tidal forces experienced in the seconds leading up to their collision, causing the entire crust of the star to shatter.

The sources of most GRBs are billions of light years away from Earth, implying that the explosions are both extremely energetic (a typical burst releases as much energy in a few seconds as the Sun will in its entire 10-billion-year lifetime) and extremely rare (a few per galaxy per million years).

All observed GRBs have originated from outside the Milky Way galaxy, although a related class of phenomena, soft gamma repeater flares, are associated with magnetars within the Milky Way.

It has been hypothesized that a gamma-ray burst in the Milky Way, pointing directly towards the Earth, could cause a mass extinction event.

GRBs were first detected in 1967 by the Vela satellites, which had been designed to detect covert nuclear weapons tests; this was declassified and published in 1973.

Following their discovery, hundreds of theoretical models were proposed to explain these bursts, such as collisions between comets and neutron stars.

Little information was available to verify these models until the 1997 detection of the first X-ray and optical afterglows and direct measurement of their redshifts using optical spectroscopy, and thus their distances and energy outputs.

These discoveries, and subsequent studies of the galaxies and supernovae associated with the bursts, clarified the distance and luminosity of GRBs, definitively placing them in distant galaxies.

The United States suspected that the Soviet Union might attempt to conduct secret nuclear tests after signing the Nuclear Test Ban Treaty in 1963.

On July 2, 1967, at 14:19 UTC, the Vela 4 and Vela 3 satellites detected a flash of gamma radiation unlike any known nuclear weapons signature.

Uncertain what had happened but not considering the matter particularly urgent, the team at the Los Alamos National Laboratory, led by Ray Klebesadel, filed the data away for investigation.

As additional Vela satellites were launched with better instruments, the Los Alamos team continued to find inexplicable gamma-ray bursts in their data.

By analyzing the different arrival times of the bursts as detected by different satellites, the team was able to determine rough estimates for the sky positions of 16 bursts and definitively rule out a terrestrial or solar origin.

The discovery was declassified and published in 1973.

Most early theories of gamma-ray bursts posited nearby sources within the Milky Way Galaxy.

From 1991, the Compton Gamma Ray Observatory (CGRO) and its Burst and Transient Source Explorer (BATSE) instrument, an extremely sensitive gamma-ray detector, provided data that showed the distribution of GRBs is isotropicnot biased towards any particular direction in space.

If the sources were from within our own galaxy, they would be strongly concentrated in or near the galactic plane.

The absence of any such pattern in the case of GRBs provided strong evidence that gamma-ray bursts must come from beyond the Milky Way.

However, some Milky Way models are still consistent with an isotropic distribution.

In October 2018, astronomers reported that GRB 150101B and GW170817, a gravitational wave event detected in 2017, may have been produced by the same mechanism – the merger of two neutron stars.

This suggested an origin of either very faint stars or extremely distant galaxies.

Even the most accurate positions contained numerous faint stars and galaxies, and it was widely agreed that final resolution of the origins of cosmic gamma-ray bursts would require both new satellites and faster communication.

This fading emission would be called the "afterglow".

Early searches for this afterglow were unsuccessful, largely because it is difficult to observe a burst's position at longer wavelengths immediately after the initial burst.

The breakthrough came in February 1997 when the satellite BeppoSAX detected a gamma-ray burst (GRB 970228) and when the X-ray camera was pointed towards the direction from which the burst had originated, it detected fading X-ray emission.

The William Herschel Telescope identified a fading optical counterpart 20 hours after the burst.

Once the GRB faded, deep imaging was able to identify a faint, distant host galaxy at the location of the GRB as pinpointed by the optical afterglow.

Because of the very faint luminosity of this galaxy, its exact distance was not measured for several years.

Well after then, another major breakthrough occurred with the next event registered by BeppoSAX, GRB 970508.

This event was localized within four hours of its discovery, allowing research teams to begin making observations much sooner than any previous burst.

The spectrum of the object revealed a redshift of z = 0.835, placing the burst at a distance of roughly 6 billion light years from Earth.

This was the first accurate determination of the distance to a GRB, and together with the discovery of the host galaxy of 970228 proved that GRBs occur in extremely distant galaxies.

Within a few months, the controversy about the distance scale ended: GRBs were extragalactic events originating within faint galaxies at enormous distances.

The following year, GRB 980425 was followed within a day by a bright supernova (SN 1998bw), coincident in location, indicating a clear connection between GRBs and the deaths of very massive stars.

This burst provided the first strong clue about the nature of the systems that produce GRBs.

BeppoSAX functioned until 2002 and CGRO (with BATSE) was deorbited in 2000.

However, the revolution in the study of gamma-ray bursts motivated the development of a number of additional instruments designed specifically to explore the nature of GRBs, especially in the earliest moments following the explosion.

The first such mission, HETE-2, was launched in 2000 and functioned until 2006, providing most of the major discoveries during this period.

One of the most successful space missions to date, Swift, was launched in 2004 and as of 2018 is still operational.

Swift is equipped with a very sensitive gamma-ray detector as well as on-board X-ray and optical telescopes, which can be rapidly and automatically slewed to observe afterglow emission following a burst.

More recently, the Fermi mission was launched carrying the Gamma-Ray Burst Monitor, which detects bursts at a rate of several hundred per year, some of which are bright enough to be observed at extremely high energies with Fermi's Large Area Telescope.

Meanwhile, on the ground, numerous optical telescopes have been built or modified to incorporate robotic control software that responds immediately to signals sent through the Gamma-ray Burst Coordinates Network.

Some bursts are preceded by a "precursor" event, a weak burst that is then followed (after seconds to minutes of no emission at all) by the much more intense "true" bursting episode.

The light curves of some events have extremely chaotic and complicated profiles with almost no discernible patterns.

Although some light curves can be roughly reproduced using certain simplified models, little progress has been made in understanding the full diversity observed.

Many classification schemes have been proposed, but these are often based solely on differences in the appearance of light curves and may not always reflect a true physical difference in the progenitors of the explosions.

Both distributions are very broad with a significant overlap region in which the identity of a given event is not clear from duration alone.

Additional classes beyond this two-tiered system have been proposed on both observational and theoretical grounds.

These account for about 30% of gamma-ray bursts, but until 2005, no afterglow had been successfully detected from any short event and little was known about their origins.

Since then, several dozen short gamma-ray burst afterglows have been detected and localized, several of which are associated with regions of little or no star formation, such as large elliptical galaxies and the central regions of large galaxy clusters.

This rules out a link to massive stars, confirming that short events are physically distinct from long events.

In addition, there has been no association with supernovae.

The true nature of these objects was initially unknown, and the leading hypothesis was that they originated from the mergers of binary neutron stars or a neutron star with a black hole.

Such mergers were theorized to produce kilonovae, and evidence for a kilonova associated with GRB 130603B was seen.

A small fraction of short gamma-ray bursts are probably produced by giant flares from soft gamma repeaters in nearby galaxies.

The origin of short GRBs in kilonovae was confirmed when short GRB 170817A was detected only 1.7 s after the detection of gravitational wave GW170817, which was a signal from the merger of two neutron stars.

Because these events constitute the majority of the population and because they tend to have the brightest afterglows, they have been observed in much greater detail than their short counterparts.

Almost every well-studied long gamma-ray burst has been linked to a galaxy with rapid star formation, and in many cases to a core-collapse supernova as well, unambiguously associating long GRBs with the deaths of massive stars.

They have been proposed to form a separate class, caused by the collapse of a blue supergiant star, a tidal disruption event or a new-born magnetar.

Only a small number have been identified to date, their primary characteristic being their gamma ray emission duration.

The most studied ultra-long events include GRB 101225A and GRB 111209A.

The low detection rate may be a result of low sensitivity of current detectors to long-duration events, rather than a reflection of their true frequency.

An average long GRB has a bolometric flux comparable to a bright star of our galaxy despite a distance of billions of light years (compared to a few tens of light years for most visible stars).

Most of this energy is released in gamma rays, although some GRBs have extremely luminous optical counterparts as well.

GRB 080319B, for example, was accompanied by an optical counterpart that peaked at a visible magnitude of 5.8, comparable to that of the dimmest naked-eye stars despite the burst's distance of 7.5 billion light years.

This combination of brightness and distance implies an extremely energetic source.

Assuming the gamma-ray explosion to be spherical, the energy output of GRB 080319B would be within a factor of two of the rest-mass energy of the Sun (the energy which would be released were the Sun to be converted entirely into radiation).

Gamma-ray bursts are thought to be highly focused explosions, with most of the explosion energy collimated into a narrow jet.

Observations suggest significant variation in the jet angle from between 2 and 20 degrees.

Because their energy is strongly focused, the gamma rays emitted by most bursts are expected to miss the Earth and never be detected.

When a gamma-ray burst is pointed towards Earth, the focusing of its energy along a relatively narrow beam causes the burst to appear much brighter than it would have been were its energy emitted spherically.

When this effect is taken into account, typical gamma-ray bursts are observed to have a true energy release of about 1044 J, or about 1/2000 of a Solar mass () energy equivalentwhich is still many times the mass-energy equivalent of the Earth (about 5.5 × 1041 J).

This is comparable to the energy released in a bright type Ib/c supernova and within the range of theoretical models.

Very bright supernovae have been observed to accompany several of the nearest GRBs.

Additional support for focusing of the output of GRBs has come from observations of strong asymmetries in the spectra of nearby type Ic supernova and from radio observations taken long after bursts when their jets are no longer relativistic.

Short (time duration) GRBs appear to come from a lower-redshift (i.e.

The association of some long GRBs with supernovae and the fact that their host galaxies are rapidly star-forming offer very strong evidence that long gamma-ray bursts are associated with massive stars.

The most widely accepted mechanism for the origin of long-duration GRBs is the collapsar model, in which the core of an extremely massive, low-metallicity, rapidly rotating star collapses into a black hole in the final stages of its evolution.

Matter near the star's core rains down towards the center and swirls into a high-density accretion disk.

The infall of this material into a black hole drives a pair of relativistic jets out along the rotational axis, which pummel through the stellar envelope and eventually break through the stellar surface and radiate as gamma rays.

Some alternative models replace the black hole with a newly formed magnetar, although most other aspects of the model (the collapse of the core of a massive star and the formation of relativistic jets) are the same.

The closest analogs within the Milky Way galaxy of the stars producing long gamma-ray bursts are likely the Wolf–Rayet stars, extremely hot and massive stars, which have shed most or all of their hydrogen envelope.

Eta Carinae, Apep, and WR 104 have been cited as possible future gamma-ray burst progenitors.

It is unclear if any star in the Milky Way has the appropriate characteristics to produce a gamma-ray burst.

The massive-star model probably does not explain all types of gamma-ray burst.

There is strong evidence that some short-duration gamma-ray bursts occur in systems with no star formation and no massive stars, such as elliptical galaxies and galaxy halos.

The favored theory for the origin of most short gamma-ray bursts is the merger of a binary system consisting of two neutron stars.

According to this model, the two stars in a binary slowly spiral towards each other because gravitational radiation releases energy until tidal forces suddenly rip the neutron stars apart and they collapse into a single black hole.

The infall of matter into the new black hole produces an accretion disk and releases a burst of energy, analogous to the collapsar model.

Numerous other models have also been proposed to explain short gamma-ray bursts, including the merger of a neutron star and a black hole, the accretion-induced collapse of a neutron star, or the evaporation of primordial black holes.

This event had a gamma-ray duration of about 2 days, much longer than even ultra-long GRBs, and was detected in X-rays for many months.

It occurred at the center of a small elliptical galaxy at redshift z = 0.3534.

There is an ongoing debate as to whether the explosion was the result of stellar collapse or a tidal disruption event accompanied by a relativistic jet, although the latter explanation has become widely favoured.

A tidal disruption event of this sort is when a star interacts with a supermassive black hole, shredding the star, and in some cases creating a relativistic jet which produces bright emission of gamma ray radiation.