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1.
Nature ; 629(8010): 58-61, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38658757

RESUMO

Magnetar giant flares are rare explosive events releasing up to 1047 erg in gamma rays in less than 1 second from young neutron stars with magnetic fields up to 1015-16 G (refs. 1,2). Only three such flares have been seen from magnetars in our Galaxy3,4 and in the Large Magellanic Cloud5 in roughly 50 years. This small sample can be enlarged by the discovery of extragalactic events, as for a fraction of a second giant flares reach luminosities above 1046 erg s-1, which makes them visible up to a few tens of megaparsecs. However, at these distances they are difficult to distinguish from short gamma-ray bursts (GRBs); much more distant and energetic (1050-53 erg) events, originating in compact binary mergers6. A few short GRBs have been proposed7-11, with different amounts of confidence, as candidate giant magnetar flares in nearby galaxies. Here we report observations of GRB 231115A, positionally coincident with the starburst galaxy M82 (ref. 12). Its spectral properties, along with the length of the burst, the limits on its X-ray and optical counterparts obtained within a few hours, and the lack of a gravitational wave signal, unambiguously qualify this burst as a giant flare from a magnetar in M82.

2.
Wiad Lek ; 73(8): 1626-1631, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33055323

RESUMO

OBJECTIVE: The aim: Grounding on the electronic microscopy of PT make conclusions about the tonsil activity in adults depending on the accompanied pathology of nose and PS. PATIENTS AND METHODS: Materials and methods: Ultramicroscopic examination of 111 patients with PT hypertrophy aged 18-55 was done. Depending on the nose and PS pathology (inflammatory, non-inflammatory) patients' PS biopsic materials were distributed into 2 groups: 58 cases on inflammatory and 53 on non-inflammatory background. The control group consisted of 24 patients aged 18 without nose and PS pathology. The images of ultrathin PT sections were received with the help of transmission electronic microscope PEM - 125 with digital camera (SELMI, Sumy). RESULTS: Results: Great variations in PT cell condition, depending on the pathology were distinguished. Features of the adenoiditis in inflammatory and non-inflammatory diseases of nose and PS were proved. CONCLUSION: Conclusions: 1. PT ultra-microscopy in control group shows great activity of lymphocytes and high energy exchange of cells, with prevailing B-lymphocyte population. 2. The complex of PT ultra structural changes while nose and PS inflammatory diseases shows the activation of immune reaction in competent cells with T-lymphocyte increase in patients older than 25, which witnesses chronic inflammation. 3. In group with nose and PT non-inflammatory diseases, activity of PT B-lymphocytes is unchanged accompanied by the T-lymphocytes growth, which is also characteristic for chronic inflammation.


Assuntos
Tonsila Faríngea , Seios Paranasais , Adolescente , Adulto , Humanos , Inflamação , Pessoa de Meia-Idade , Cavidade Nasal , Nariz , Adulto Jovem
3.
Artigo em Inglês | MEDLINE | ID: mdl-32753777

RESUMO

CONTEXT: In July 2015, the high-mass X-ray binary V0332+53 underwent a giant outburst, a decade after the previous one. V0332+53 hosts a strongly magnetized neutron star. During the 2004-2005 outburst, an anti-correlation between the centroid energy of its fundamental cyclotron resonance scattering features (CRSFs) and the X-ray luminosity was observed. AIMS: The long (≈ 100 d) and bright (L x ≈ 1038 erg s-1) 2015 outburst offered the opportunity to study during another outburst the unique properties of the fundamental CRSF and its dependence on the X-ray luminosity. METHODS: The source was observed by the INTEGRAL satellite for ~ 330 ks. We exploit the spectral resolution at high energies of the SPectrometer on INTEGRAL (SPI) and the Joint European X-ray Monitors to characterize its spectral properties, focusing in particular on the CRSF-luminosity dependence. We complement the data of the 2015 outburst with those collected by SPI in 2004-2005 and left unpublished so far. RESULTS: We find a highly significant anti-correlation of the centroid energy of the fundamental CRSF and the 3 -100 keV luminosity of E 1 ∝ -0.095(8)L 37 keV. This trend is observed for both outbursts. We confirm the correlation between the width of the fundamental CRSF and the X-ray luminosity previously found in the JEM-X and IBIS dataset of the 2004-2005 outburst. By exploiting the RXTE/ASM and Swift/BAT monitoring data we also report on the detection of a ~ 34 d modulation superimposed on the mean profiles and roughly consistent with the orbital period of the pulsar. We discuss possible interpretations of such variability.

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