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2.
Nature ; 612(7940): 430-434, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36450988

RESUMO

Tidal disruption events (TDEs) are bursts of electromagnetic energy that are released when supermassive black holes at the centres of galaxies violently disrupt a star that passes too close1. TDEs provide a window through which to study accretion onto supermassive black holes; in some rare cases, this accretion leads to launching of a relativistic jet2-9, but the necessary conditions are not fully understood. The best-studied jetted TDE so far is Swift J1644+57, which was discovered in γ-rays, but was too obscured by dust to be seen at optical wavelengths. Here we report the optical detection of AT2022cmc, a rapidly fading source at cosmological distance (redshift z = 1.19325) the unique light curve of which transitioned into a luminous plateau within days. Observations of a bright counterpart at other wavelengths, including X-ray, submillimetre and radio, supports the interpretation of AT2022cmc as a jetted TDE containing a synchrotron 'afterglow', probably launched by a supermassive black hole with spin greater than approximately 0.3. Using four years of Zwicky Transient Facility10 survey data, we calculate a rate of [Formula: see text] per gigapascals cubed per year for on-axis jetted TDEs on the basis of the luminous, fast-fading red component, thus providing a measurement complementary to the rates derived from X-ray and radio observations11. Correcting for the beaming angle effects, this rate confirms that approximately 1 per cent of TDEs have relativistic jets. Optical surveys can use AT2022cmc as a prototype to unveil a population of jetted TDEs.

3.
Science ; 368(6491)2020 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-32381689

RESUMO

Van den Heuvel and Tauris argue that if the red giant star in the system 2MASS J05215658+4359220 has a mass of 1 solar mass (M ☉), then its unseen companion could be a binary composed of two 0.9 M ☉ stars, making a triple system. We contend that the existing data are most consistent with a giant of mass [Formula: see text] M ☉, implying a black hole companion of [Formula: see text] M ☉.

4.
Science ; 366(6465): 637-640, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31672898

RESUMO

Black hole binary systems with companion stars are typically found via their x-ray emission, generated by interaction and accretion. Noninteracting binaries are expected to be plentiful in the Galaxy but must be observed using other methods. We combine radial velocity and photometric variability data to show that the bright, rapidly rotating giant star 2MASS J05215658+4359220 is in a binary system with a massive unseen companion. The system has an orbital period of ~83 days and near-zero eccentricity. The photometric variability period of the giant is consistent with the orbital period, indicating star spots and tidal synchronization. Constraints on the giant's mass and radius imply that the unseen companion is [Formula: see text] solar masses, indicating that it is a noninteracting low-mass black hole or an unexpectedly massive neutron star.

5.
Nucleic Acids Res ; 37(Database issue): D852-7, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18996892

RESUMO

INTERFEROME is an open access database of types I, II and III Interferon regulated genes (http://www.interferome.org) collected from analysing expression data sets of cells treated with IFNs. This database of interferon regulated genes integrates information from high-throughput experiments with annotation, ontology, orthologue sequences from 37 species, tissue expression patterns and gene regulatory information to enable a detailed investigation of the molecular mechanisms underlying IFN biology. INTERFEROME fulfils a need in infection, immunity, development and cancer research by providing computational tools to assist in identifying interferon signatures in gene lists generated by high-throughput expression technologies, and their potential molecular and biological consequences.


Assuntos
Bases de Dados Genéticas , Regulação da Expressão Gênica , Interferons/farmacologia , Animais , Perfilação da Expressão Gênica , Humanos , Camundongos , Análise de Sequência com Séries de Oligonucleotídeos , Regiões Promotoras Genéticas , Proteômica
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