A month of monitoring the new magnetar Swift J1555.2-5402 during an X-ray outburst

Simple item page
dc.contributor.authorEnoto, Teruaki
dc.contributor.authorNg, Mason
dc.contributor.authorHu, Chin-ping
dc.contributor.authorGuver, Tolga
dc.contributor.authorJaisawal, Gaurava K.
dc.contributor.authorO'Connor, Brendan
dc.contributor.authorGogus, Ersin
dc.contributor.authorLien, Amy
dc.contributor.authorKisaka, Shota
dc.contributor.authorWadiasingh, Zorawar
dc.contributor.authorMajid, Walid A.
dc.contributor.authorPearlman, Aaron B.
dc.contributor.authorArzoumanian, Zaven
dc.contributor.authorBansal, Karishma
dc.contributor.authorBlumer, Harsha
dc.contributor.authorChakrabarty, Deepto
dc.contributor.authorGendreau, Keith
dc.contributor.authorHo, Wynn C. G.
dc.contributor.authorKouveliotou, Chryssa
dc.contributor.authorRay, Paul S.
dc.contributor.authorStrohmayer, Tod E.
dc.contributor.authorYounes, George
dc.contributor.authorPalmer, David M.
dc.contributor.authorSakamoto, Takanori
dc.contributor.authorAkahori, Takuya
dc.contributor.authorEie, Sujin
dc.date.accessioned2021-08-18T18:20:09Z
dc.date.available2021-08-18T18:20:09Z
dc.date.issued2021-08-06
dc.description.abstractThe soft gamma-ray repeater Swift J1555.2-5402 was discovered by means of a 12-ms duration short burst detected with Swift BAT on 2021 June 3. Then 1.6 hours after the first burst detection, NICER started daily monitoring of this X-ray source for a month. The absorbed 2-10 keV flux stays nearly constant at around 4e-11 erg/s/cm2 during the monitoring timespan, showing only a slight gradual decline. A 3.86-s periodicity is detected, and the time derivative of this period is measured to be 3.05(7)e-11 s/s. The soft X-ray pulse shows a single sinusoidal shape with a root-mean-square pulsed fraction that increases as a function of energy from 15% at 1.5 keV to 39% at 7 keV. The equatorial surface magnetic field, characteristic age, and spin-down luminosity are derived under the dipole field approximation to be 3.5e+14 G, 2.0 kyr, and 2.1e+34 erg/s, respectively. An absorbed blackbody with a temperature of 1.1 keV approximates the soft X-ray spectrum. Assuming a source distance of 10 kpc, the peak X-ray luminosity is ~8.5e+35 erg/s in the 2--10 keV band. During the period of observations, we detect 5 and 37 short bursts with Swift/BAT and NICER, respectively. Based on these observational properties, especially the inferred strong magnetic field, this new source is classified as a magnetar. We also coordinated hard X-ray and radio observations with NuSTAR, DSN, and VERA. A hard X-ray power-law component that extends up to at least 40 keV is detected at 3-sigma significance. The 10-60 keV flux, which is dominated by the power-law component, is ~9e-12 erg/s/cm2 with a photon index of ~1.2. The pulsed fraction has a sharp cutoff above 10 keV, down to ~10% in the hard-tail component band. No radio pulsations are detected during the DSN nor VERA observations. We place 7{\sigma} upper limits of 0.043mJy and 0.026 mJy on the flux density at S-band and X-band, respectively.en_US
dc.description.sponsorshipThe authors are grateful to the NICER, NuSTAR, Swift, and DSN scheduling and operation teams. We thank Francesco Coti Zelati, Alice Borghese, Nanda Rea, Gian Luca Israel, and Paolo Esposito for helpful discussion about the initial observation and for preparing the GCN reports. We thank Mareki Honma, Takaaki Jike, Aya Yamauchi, Toshio Terasawa, and Tomoya Hirota for useful comments on the VERA observation and all the staff of Mizusawa VLBI Observatory of NAOJ for operating the VERA array. T.E. and S.K. are supported by JSPS/MEXT KAKENHI grant numbers 17K18776, 18H04584, 18H01246, 19K14712 and 21H01078. A.B.P is a McGill Space Institute (MSI) Fellow and a Fonds de Recherche du Quebec – Nature et Technologies (FRQNT) postdoctoral fellow. W.C.G.H. acknowledges support through grant 80NSSC20K0278 from NASA. NICER research at NRL is supported by NASA. W.A.M is grateful to the DSN scheduling team and the Canberra Deep Space Communication Complex (CDSCC) staff for scheduling and carrying the radio observations with the DSN. A portion of this research was performed at the Jet Propulsion Laboratory, California Institute of Technology, under a Research and Technology Development Grant through a contract with the National Aeronautics and Space Administration. U.S. government sponsorship is acknowledgeden_US
dc.description.urihttps://arxiv.org/abs/2108.02939en_US
dc.format.extent26 pagesen_US
dc.genrejournal articlesen_US
dc.genrepreprintsen_US
dc.identifierdoi:10.13016/m2pq1q-w4s5
dc.identifier.urihttp://hdl.handle.net/11603/22538
dc.language.isoen_USen_US
dc.relation.isAvailableAtThe University of Maryland, Baltimore County (UMBC)
dc.relation.ispartofUMBC Physics Department Collection
dc.rightsThis item is likely protected under Title 17 of the U.S. Copyright Law. Unless on a Creative Commons license, for uses protected by Copyright Law, contact the copyright holder or the author.en_US
dc.titleA month of monitoring the new magnetar Swift J1555.2-5402 during an X-ray outbursten_US
dc.typeTexten_US
dcterms.creatorhttps://orcid.org/0000-0002-7851-9756en_US

Files

Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
2108.02939.pdf
Size:
936.02 KB
Format:
Adobe Portable Document Format
Description:
Download
License bundle
Now showing 1 - 1 of 1
No Thumbnail Available
Name:
license.txt
Size:
2.56 KB
Format:
Item-specific license agreed upon to submission
Description:
Download

Collections

UMBC Physics Department