4U 1909+07 - Revision history

Kuehnel: Created page with " '''Other names''' : X1908+075 ([http://simbad.u-strasbg.fr/simbad/sim-id?Ident=4U+1909%2B07&NbIdent=1&Radius=2&Radius.unit=arcmin&submit=submit+id Simbad],
2018-04-18T09:53:46Z

Created page with " '''Other names''' : X1908+075 ([http://simbad.u-strasbg.fr/simbad/sim-id?Ident=4U+1909%2B07&NbIdent=1&Radius=2&Radius.unit=arcmin&submit=submit+id Simbad], <ref name="Wen00a..."

New page

'''Other names''' : X1908+075 ([http://simbad.u-strasbg.fr/simbad/sim-id?Ident=4U+1909%2B07&NbIdent=1&Radius=2&Radius.unit=arcmin&submit=submit+id Simbad], <ref name="Wen00a" />)

'''Coordinates''' : RA 19h 10' 48.21'' , DEC +07° 35' 51.6'' (i.e. close to GRS 1915+105 and [[4U 1907+09]])

'''Monitoring data''':
[http://xte.mit.edu/asmlc/srcs/x1908+075.html RXTE/ASM]
[http://swift.gsfc.nasa.gov/docs/swift/results/transients/weak/4U1909p07/ Swift/BAT]
[http://maxi.riken.jp/top/index.php?cid=1&jname=J1910+075 MAXI]
[http://heastro.phys.lsu.edu/gbm/image.php?sourceimage=4U1909+07 Fermi/GBM Occultation Project]
= Binary System =

==Orbit==
'''Orbital Period''': 4.4 days from ASM and RXTE/PCA data (<ref name="Wen00a" />, <ref name="Levine04a" />)

Strong variation of N_H over the orbit, leads to contstrained inclination of 38°-72° (<ref name="Levine04a" />).

The distance of the binary system was estimated to be ∼7 kpc by <ref name="MorelGrosdidier05" />.
A newer analysis by <ref name="MartinezNunez15a" /> derives the distance to be 4.85 ± 0.50 kpc.

== Companion ==

Probably an early B-type (B0--B3) star; M_spec = 15±6M⊙ <ref name="MartinezNunez15a" />

= Description =

==Pulsations==

'''Pulse Period''': ~604sec, changing in a random walk like manner (<ref name="Levine04a" />, <ref name="Fuerst09a" />)

[[File:para_evol.png|200px]]
Plot shows period measurements from RXTE data (<ref name="Levine04a" />) in red and from INTEGRAL data (<ref name="Fuerst09a" />) in black).

'''Pulse profile''': strongly energy dependent:

[[File:pp_int_rxte.png|200px]]
Plot shows pulse profiles from RXTE/PCA in black in panels ''a-c'', a RXTE/HEXTE profile in panel ''d'' in black and a INTEGRAL/ISGRI profile in panel ''d'' in red (<ref name="Fuerst09a" />).

==Spectrum==

Well described with a ''phabs*(cutoffpl+gauss)'' model, additional ''bbody'' improves χ² esepecially in phase resolved analysis (<ref name="Fuerst09a" />)

[[File:low_cutoffpl_bbody_int2.png|200px]]
Plot panel ''a'' shows the RXTE/PCA spectrum in red, RXTE/HEXTE in green, INTEGRAL/ISGRI in blue. Panel ''b'' shows residuals without a blackbody component, ''c'' with the blackbody (<ref name="Fuerst09a" />).

Claimed '''Compton shoulder''' in ''Chandra'' data on the iron Kα line (<ref name="Torrejon10a" />).

'''CRSF''': none known (RXTE and INTEGRAL data)

==Further data==
'''Suzaku''' 25ksec observations to be done in AO5.

'''References'''