Találati lista | Tudóstér

001-es BibID:	BIBFORM117707
035-os BibID:	(Scopus)85179888189 (WoS)001119369400011
Első szerző:	Horváth István
Cím:	Mapping the Universe with gamma-ray bursts / Istvan Horvath, Zsolt Bagoly, Lajos G. Balazs, Jon Hakkila, Zsuzsa Horvath, Andras Peter Joo, Sandor Pinter, L. Viktor Tóth, Peter Veres, Istvan I. Racz
Dátum:	2024
ISSN:	0035-8711
Megjegyzések:	We explore large-scale cosmic structure using the spatial distribution of 542 gamma-ray bursts (GRBs) having accurately measured positions and spectroscopic redshifts. Prominent cosmological clusters are identified in both the northern and southern galactic hemispheres (avoiding extinction effects in the plane of the Milky Way) using the bootstrap point-radius method. The northern galactic hemisphere contains a significant group of four GRBs in the redshift range 0.59 ? z ? 0.62 (with a bootstrap probability of p = 0.012) along with the previously identified Hercules-Corona Borealis Great Wall (in the revised redshift range 0.9 ? z ? 2.1; p = 0.017). The southern galactic hemisphere contains the previously identified Giant GRB Ring (p = 0.022) along with another possible cluster of seven to nine GRBs at 1.17 ? z ? 1.444 (p = 0.031). Additionally, both the Hercules-Corona Borealis Great Wall and the Giant GRB Ring have become more prominent as the GRB sample size has grown. The approach used here underscores the potential value of GRB clustering as a probe of large-scale cosmic structure, complementary to galaxy and quasar clustering. Because of the vast scale on which GRB clustering provides valuable insights, it is important that optical GRB monitoring continues so that additional spectroscopic redshift measurements could be obtained.
Tárgyszavak:	Természettudományok Fizikai tudományok idegen nyelvű folyóiratközlemény külföldi lapban folyóiratcikk methods: data analysis methods: statistical gamma-ray burst: general large-scale structure of Universe cosmology observations gamma-ray bursts
Megjelenés:	Monthly Notices Of The Royal Astronomical Society. - 527 : 3 (2024), p. 7191-7202. -
További szerzők:	Bagoly Zsolt Balázs Lajos G. Hakkila, Jon Horváth Zsuzsa Joó András Péter Pintér Sándor Tóth L. Viktor (1964-) (csillagász) Veres Péter Rácz István
Pályázati támogatás:	OTKA K134257 OTKA
Internet cím:	Szerző által megadott URL DOI Intézményi repozitóriumban (DEA) tárolt változat
Borító:
Saját polcon:

001-es BibID:	BIBFORM117885
035-os BibID:	(Scopus)85181763784
Első szerző:	Pintér Sándor (Szeged)
Cím:	Some statistical remarks on GRBs jointly detected by Fermi and Swift satellites / Sandor Pinter, Lajos G. Balazs, Zsolt Bagoly, L. Viktor Toth, Istvan I. Racz, Istvan Horvath
Dátum:	2024
ISSN:	0035-8711
Megjegyzések:	We made statistical analysis of the Fermi GBM and Swift BAT observational material, accumulated over 15 yr. We studied how GRB parameters (T90 duration, fluence, and peak flux) that were observed by only one satellite differ from those observed by both. In the latter case, it was possible to directly compare the values of the parameters that both satellites measured. The GRBs measured by both satellites were identified using the k-nearest neighbours algorithm in Euclidean distance. In the parameter space we determined the direction in which the jointly detected GRBs differ most from those detected by only one of the instruments using linear discriminant analyses. To get the strength of the relationship between the parameters obtained from the GBM and BAT, a canonical correlation was performed. The GBM and BAT T90 distributions were fitted with a linear combination of lognormal functions. The optimal number of such functions required for fit is two for GBM and three for BAT. Contrary to the widely accepted view, we found that the number of lognormal functions required for fitting the observed distribution of GRB durations does not allow us to deduce the number of central engine types responsible for GRBs.
Tárgyszavak:	Természettudományok Fizikai tudományok idegen nyelvű folyóiratközlemény külföldi lapban folyóiratcikk gamma-ray burst: general instrumentation: detectors methods: statistical space vehicles: instruments telescopes
Megjelenés:	Monthly Notices Of The Royal Astronomical Society. - 527 : 3 (2024), p. 8931-8940. -
További szerzők:	Balázs Lajos G. Bagoly Zsolt Tóth L. Viktor (1964-) (csillagász) Rácz István (fizikus, csillagászat) Horváth István
Pályázati támogatás:	K-146092 OTKA
Internet cím:	Szerző által megadott URL DOI Intézményi repozitóriumban (DEA) tárolt változat
Borító:
Saját polcon: