A gigantic flare from the star, Cluster Trumpler 14 Y 422, in the Carina nebula

Summary

  • XMM-Newton, NuSTAR and Swift observations of the Carina star forming complex detected an X-ray flare from the star, Trumpler 14 Y 442, on 2015 July 16.

Investigators

  • Kenji Hamaguchi (CRESST NASA/GSFC & UMBC)
  • Stephen A. Drake, Michael F. Corcoran (CRESST NASA/GSFC & USRA)
  • Mairan Teodoro (NASA/GSFC, Western Michigan University & CNPq)
  • Noel Richardson (Universite de Montreal)

X-ray Observations in 2015

  • July 16
    • XMM-Newton (ObsID: 0762910401, exp: 11.5 ksec, elapsed time: ~11.5 ksec)
    • NuSTAR (ObsID: 30101005002, exp: 23.6 ksec, elapsed time: ~38.7 ksec)
    • Swift (ObsID: 00081578001, exp: 2 ksec, elapsed time: 5.8 ksec)
  • July 28-31
    • Swift (ObsID: 00031097045-7, exp: 4.6 ksec)
  • August 21
    • Swift (ObsID: 00031097049, exp: 9.1 ksec)

Parameters of the flare source

  • (R.A., Dec)[J2000] = (10 44 02.80, -59 39 46.7)
    • Measured from the XMM-Newton MOS images on July 16
    • 0.3" from the star, Trumpler 14 Y 442 (SIMBAD)
  • Fx [0.5-10 keV] = 4.67e-12 ergs s-1 cm-2 on July 16 (during the XMM-Newton observation)
    • Lx = 2.96e+33 ergs s-1 assuming the distance at the Carina nebula (2.3 kpc)

X-ray Image

  • XMM-Newton EPIC/MOS2 image on July 16 (0.3-10 keV: left) and Swift XRT image on July 28-31 (0.3-8 keV: right).
    • The white arrow on the image points at the flare source.
    • On the Swift image, Eta Carinae has a black spot at the center due to photon pile-ups.
XMM image of the X-ray flare source on 2015 July 16 Swift image of the X-ray flare source on 2015 July 28-31

X-ray light curves

  • NuSTAR/FPMA+B 3-25 keV light curve (0.3-10 keV, top) and XMM-Newton 0.3-10 keV light curve (3-25 keV: bottom) on July 16

XMM-Newton and NuSTAR light curves

X-ray spectra

  • Simultaneous fit to the XMM-Newton and NuSTAR spectra on July 16
  • Model: apec * TBabs
    • The model normalizations for the XMM-Newton and NuSTAR spectra are varied because the flux changed through the observation.
    • Z = 1.0 solar (frozen)
  • Best-fit result:
    • kT = 8.3 (7.5-9.7) keV
    • nH = 1.9e21 (1.6e21-2.2e21) cm-2
    • reduced chi-square: 0.95 (dof = 283)
XMM-Newton and NuSTAR spectra of the flare source

UV/Optical/IR data

  • Photometric data
    • UBVI (Johnson)
    • GRI (Sloan SDSS)
    • JHK (2MASS)
    • [3.6, 4.5, 5.8, 8.0] um (Spitzer IRAC)
    • [3.4, 4.6] um (WISE)
  • Model
  • Best-fit result
    • Teff = ~4750K
    • Av = ~0.7
SED fitting

NASA Logo, National Aeronautics and Space Administration
Goddard