A Comparative Study of Long and Short Grbs. I. Overlapping Properties

Li, Ye; Zhang, Bing; Lü, Hou-Jun

doi:10.3847/0067-0049/227/1/7

Cited by 77 publications

(78 citation statements)

References 282 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We compare the host galaxy properties of XT1 and XT2 with those of redshift-binned SGRBs and long GRBs (LGRBs) in Figure 5. The host galaxy data of GRBs are adopted from Li et al (2016b) and references therein (e.g., 2009;Fong et al 2013;Blanchard et al 2016). They are presented in both the specific star formation rate (sSFR)stellar mass (M * ) plane and the offset -half-light radius R 50 plane.…”

Section: Host Galaxy Propertiesmentioning

confidence: 99%

“…The offset of XT1 belongs to the lower end of the offset distribution of SGRBs. The lower panel of Figure 5 describes O(II : I) host , representing the "odds" or probabilities that the sources belong to the LGRB (massive-star core collapse type, or Type II) vs. SGRB (compact-star merger type, or Type I) populations based on the statistical properties of the host-galaxy data of the two types (Li et al 2016b). As pointed out by Xue et al (2019), the O(II : I) host of XT2 falls right on the peak of the distribution of SGRBs.…”

Section: Host Galaxy Propertiesmentioning

confidence: 99%

See 1 more Smart Citation

A Unified Binary Neutron Star Merger Magnetar Model for the Chandra X-Ray Transients CDF-S XT1 and XT2

Sun

Zhang

et al. 2019

ApJ

Self Cite

View full text Add to dashboard Cite

Two bright X-ray transients were reported from the Chandra Deep Field South archival data, namely CDF-S XT1 and XT2. Whereas the nature of the former is not identified, the latter was suggested as an excellent candidate for a rapidly spinning magnetar born from a binary neutron star (BNS) merger. Here we propose a unified model to interpret both transients within the framework of the BNS merger magnetar model. According to our picture, CDF-S XT2 is observed from the "free zone" where the magnetar spindown powered X-ray emission escapes freely, whereas CDF-S XT1 originates from the "trapped zone" where the X-ray emission is initially blocked by the dynamical ejecta and becomes transparent after the ejecta is pushed to a distance where Thomson optical depth drops below unity. We fit the magnetar model to the light curves of both transients and derived consistent parameters for the two events, with magnetic field, initial spin period and X-ray emission efficiency being (B p = 10 16 G, P = 1.2 ms, η = 0.001) and (B p = 10 15.8 G, P = 4.4 ms, η = 0.001) for XT1 and XT2, respectively. The "isotropic equivalent" ejecta mass of XT1 is M ej ∼ 10 −3 M , while it is not constrained for XT2. Our results suggest that more extreme magnetar parameters are required to have XT1 detected from the trapped zone. The model parameters for both events are generally consistent with those derived from SGRB X-ray plateau observations. The host galaxy properties of both transients are also consistent with those of SGRBs. The event rate densities of both XT1 and XT2 are consistent with that of BNS mergers.

show abstract

Section: Host Galaxy Propertiesmentioning

confidence: 99%

Section: Host Galaxy Propertiesmentioning

confidence: 99%

A Unified Binary Neutron Star Merger Magnetar Model for the Chandra X-Ray Transients CDF-S XT1 and XT2

Sun

Zhang

et al. 2019

ApJ

Self Cite

View full text Add to dashboard Cite

show abstract

“…The division into these two phenomenological classes was first observed in the duration distribution by Mazets et al (1981). Nowadays, the threshold is set at T 90 2 s (Kouveliotou et al 1993), where T 90 is the time during which 90% of the GRB's fluence is accumulated (Fynbo et al 2006;King et al 2007;Kann et al 2011;Li et al 2016). The ratio of short to long GRBs is different for each satellite (9−28% of observed GRBs are short), and hence the threshold of 2 s is not robust (Bromberg et al 2013;Tarnopolski 2015a).…”

Section: Introductionmentioning

confidence: 99%

Multivariate Analysis of BATSE Gamma-Ray Burst Properties Using Skewed Distributions

Tarnopolski

2019

ApJ

View full text Add to dashboard Cite

The number of classes of gamma-ray bursts (GRBs), besides the well-established short and long ones, remains a debatable issue. It was already shown, however, that when invoking skewed distributions, the log T 90 and log T 90 −log H 32 spaces are adequately modeled with mixtures of only two such components, implying two GRB types. Herein, a comprehensive multivariate analysis of several multi-dimensional parameter spaces is conducted for the BATSE sample of GRBs, with the usage of skewed distributions. It is found that the number of extracted components varies between the examined parameter sets, and ranges from 2 to 4, with higher-dimensional spaces allowing for more classes. A Monte Carlo testing implies that these additional components are likely to be artifacts owing to the finiteness of the data and be a result of examining a particular realization of the data as a random sample, resulting in spurious identifications.

show abstract

“…To discern better whether CDF-S XT2 has an NS-NS merger origin, we calculate the probability, O(II:I) host , of the source being similar to long GRB (LGRB: massive star collapse type or Type II) versus SGRB (compact star merger type or Type I) populations based on the statistical properties of the host galaxy data of the two types 15,26,27 . The criteria used include how each of the following observed parameters compares with the distributions of both LGRBs and SGRBs collected 27 : stellar mass, SFR, metallicity, offset, and galaxy size.…”

mentioning

confidence: 99%

A magnetar-powered X-ray transient as the aftermath of a binary neutron-star merger

Xue

Zheng

et al. 2019

Nature

121

168

View full text Add to dashboard Cite

Neutron star-neutron star mergers are known to be associated with short gammaray bursts 1-4 . If the neutron star equation of state is sufficiently stiff, at least some of such mergers will leave behind a supramassive or even a stable neutron star that spins rapidly with a strong magnetic field (i.e., a magnetar) 5-8 . Such a magnetar signature may have been observed as the X-ray plateau following a good fraction (up to 50%) of short gamma-ray bursts 9, 10 , and it has been expected that one may observe short gamma-ray burst-less X-ray transients powered by double neutron star mergers 11, 12 . A fast X-ray transient (CDF-S XT1) was recently found to be associated with a faint host galaxy whose redshift is unknown 13 . Its X-ray and host-galaxy properties allow several possible explanations including a short gamma-ray burst seen off axis, a low-luminosity gamma-ray burst at high redshift, or a tidal disruption event involving an intermediate mass black hole and a white dwarf 13 . Here we report a second X-ray transient, CDF-S XT2, that is associated with a galaxy at redshift z = 0.738 14 .The light curve is fully consistent with being powered by a millisecond magnetar. More intriguingly, CDF-S XT2 lies in the outskirts of its star-forming host galaxy with a moderate offset from the galaxy center, as short bursts often do 15,16 . The estimated event rate density of similar X-ray transients, when corrected to the local value, is consistent with the double neutron star merger rate density inferred from the detection of GW170817 1 .Upon the completion of the deepest X-ray survey to date, the 7 Ms Chandra Deep Field-

show abstract

A Comparative Study of Long and Short Grbs. I. Overlapping Properties

Cited by 77 publications

References 282 publications

A Unified Binary Neutron Star Merger Magnetar Model for the Chandra X-Ray Transients CDF-S XT1 and XT2

A Unified Binary Neutron Star Merger Magnetar Model for the Chandra X-Ray Transients CDF-S XT1 and XT2

Multivariate Analysis of BATSE Gamma-Ray Burst Properties Using Skewed Distributions

A magnetar-powered X-ray transient as the aftermath of a binary neutron-star merger

Contact Info

Product

Resources

About