English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Tools annual

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Presents the access of premium content as premium feature

Premium Content

Global: Zendy Plus annual

Global: Zendy Free Plan

Determining the kinds of gamma-ray bursts (GRBs) has been of interest toastronomers for many years. We analyzed 1599 GRBs from the Burst and TransientSource Experiment (BATSE) 4Br catalogue using $t$-mixtures-model-basedclustering on all nine observed parameters ($T_{50}$, $T_{90}$, $F_1$, $F_2$,$F_3$, $F_4$, $P_{64}$, $P_{256}$, $P_{1024}$) and found evidence of five typesof GRBs. Our results further refine the findings of Chattopadhyay and Maitra(2017) by providing groups that are more distinct. Using the Mukherjee et al.(1998) classification scheme, also used by Chattopadhyay and Maitra (2017), ofduration, total fluence ($F_t = F_1 + F_2 + F_3 + F_4$)) and spectrum (usingHardness Ratio $H_{321} = F_3/(F_1 + F_2)$) our five groups are classified aslong-intermediate-intermediate, short-faint-intermediate, short-faint-soft,long-bright-hard, and long-intermediate-hard. We also classify 374 GRBs in theBATSE catalogue that have incomplete information in some of the observedvariables (mainly the four time integrated fluences $F_1$, $F_2$, $F_3$ and$F_4$) to the five groups obtained, using the 1599 GRBs having completeinformation in all the observed variables. Our classification scheme puts 138GRBs in the first group, 52 GRBs in the second group, 33 GRBs in the thirdgroup, 127 GRBs in the fourth group and 24 GRBs in the fifth group.

monthly notices of the royal astronomical society

Multivariate $t$-Mixtures-Model-based Cluster Analysis of BATSE Catalog  Establishes Importance of All Observed Parameters, Confirms Five Distinct  Ellipsoidal Sub-populations of Gamma Ray Bursts