NASA/IPAC EXTRAGALACTIC DATABASE
Date and Time of the Query: 2019-04-19 T13:39:38 PDT
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Notes for object MESSIER 062

2 note(s) found in NED.


1. 2001A&A...368..137V
Re:NGC 6266
3.23 NGC 6266/M 62
Two PSPC observations of the low-mass X-ray binary, burster and transient,
MXB 1659-29 contain this globular cluster in the field of view. The
transient is not detected in either observation, but the globular cluster
is in both! (The upper limit to the countrate of MXB 1659-29 in channels
50-240 is 0.6 cts ksec^-1^ in 1991, 0.9 cts ksec^-1^ in 1992; for
N_H_ ~ 2 x 10^22^ cm^-2^ - as determined from the X-ray spectrum during the
active stage by Wachter et al. (2000) - and an assumed 0.3 keV blackbody
spectrum - typical for a quiescent transient - the 1991 limit corresponds
to an upper limit to the luminosity in the 0.5-2.5 keV band of about
1.4 x 10^33^ erg s^-1^ at 10kpc.) The countrate and spectrum of the cluster
source is not significantly different between the 1991 and 1992
observations. I therefore analyse the spectrum of the combined image. As
shown in Fig. 3, the spectrum is soft, and affected by strong absorption.
Fixing the absorption column at N_H_ = 2.6 x 10^21^ cm^-2^, as indicated
by the visual absorption of the cluster, I find that a bremsstrahlung
spectrum of 0.95 +/- 0.17 keV describes the spectrum; the observed
countrate corresponds to a luminosity in the 0.5-2.5 keV range of
L_x_ ~ 1.6 x 10^33^ erg s^-1^ at the distance of 5 kpc of the cluster. Thus
spectrum and luminosity of the source are similar to what is observed in
soft X-ray transients with a neutron star in quiescence (e.g. Aql X-1,
Verbunt et al. 1994).
Two sources in the field of view and with well determined positions of
the ROSAT PSPC have an counterpart at other wavelengths: X8 with the radio
source PKS 1657-298 and X12 with the star TYC 73603941 (CD-2913096), a
binary with V = 10.1. The positions of the X-ray sources coincide within
3" and 1" with the Parkes radio source and Tycho Catalogue object,
respectively. Since both X12 and the cluster source X14 are indicated to
be extended sources by the EXSAS software in the individual 1991 and 1992
images, the actual accuracy of the position may be worse than the
positional coincidences suggest; and I have not applied a bore sight
correction based on these identifications. Confirmation that both sources
are extended would be interesting, both for the binary and for the cluster
source.

2. 1918PLicO..13....9C
Re:NGC 6266
Bright globular cluster, greatly condensed at center; this central part is 1.5'
in diameter; main part of cluster 6'. 0 s.n.


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