J/ApJS/187/388 A XMM-Newton survey of the SXRB (Henley+, 2010)
An XMM-Newton survey of the soft X-ray background.
I. The O VII and O VIII lines between l = 120° and l = 240°.
Henley D.B., Shelton R.L.
<Astrophys. J. Suppl. Ser., 187, 388-408 (2010)>
=2010ApJS..187..388H 2010ApJS..187..388H
ADC_Keywords: X-ray sources ; Surveys ; Spectroscopy
Keywords: surveys - X-rays: diffuse background - X-rays: ISM
Abstract:
We present measurements of the soft X-ray background (SXRB) OVII and
OVIII intensity between l=120° and l=240°, the first results
of a survey of the SXRB using archival XMM-Newton observations. We do
not restrict ourselves to blank-sky observations, but instead use as
many observations as possible, removing bright or extended sources by
hand if necessary. In an attempt to minimize contamination from
near-Earth solar wind charge exchange (SWCX) emission, we remove times
of high solar wind proton flux from the data. Without this filtering
we are able to extract measurements from 586 XMM-Newton observations.
With this filtering, ∼1/2 of the observations are rendered unusable,
and we are able to extract measurements from 303 observations. The
oxygen intensities are typically ∼0.5-10 photons/cm2/s/sr (line
units, L.U.) for OVII and ∼0-5L.U. for OVIII. The proton flux
filtering does not systematically reduce the oxygen intensities
measured from a given observation. However, the filtering does
preferentially remove the observations with higher oxygen intensities.
Our data set includes 69 directions with multiple observations, whose
oxygen intensity variations can be used to constrain SWCX models.
After removing observations likely to be contaminated by heliospheric
SWCX emission, we use our results to examine the Galactic halo.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 131 586 OVII (O6+) and OVIII (O7+) line intensities
(without proton flux filtering)
table2.dat 133 303 OVII (O6+) and OVIII (O7+) line intensities
(with proton flux filtering)
table5.dat 97 172 Oxygen line intensities from directions with
multiple observations
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See also:
J/ApJS/202/14 : XMM-Newton survey. II. (Henley+, 2012)
Byte-by-byte Description of file: table[12].dat
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Bytes Format Units Label Explanations
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1- 10 I010 --- XMM XMM observation identification
12- 21 A10 "YYYY/MM/DD" Obs.Date Date of the observation start
23- 29 F7.3 deg GLON Galactic longitude
31- 37 F7.3 deg GLAT Galactic latitude
39- 48 A10 ks M1exp MOS1 exposure time(s)
50- 56 A7 arcmin2 M1ome MOS1 solid angle(s)
58- 67 A10 ks M2exp MOS2 exposure time(s)
69- 75 A7 arcmin2 M2ome MOS1 solid angle(s)
77- 81 F5.2 --- IOVII OVII intensity (1)
83- 87 F5.2 --- e_IOVII Lower bound of 68% confidence interval
for IOVII (1)
89- 93 F5.2 --- E_IOVII Upper bound of 68% confidence interval
for IOVII (1)
95-100 F6.4 keV EOVII OVII model δ function's photon energy
102-106 F5.2 --- IOVIII OVIII intensity (1)
108-112 F5.2 --- e_IOVIII Lower bound of 68% confidence interval
for IOVIII (1)
114-118 F5.2 --- E_IOVIII Upper bound of 68% confidence interval
for IOVIII (1)
120-124 F5.2 10+8/cm2/s ? Averaged solar wind proton flux at
Earth (2)
126-129 F4.2 --- M/E Total model to expected 2-5keV count
rate (3)
131 A1 --- T2? [YN] Data in Table 2? (only for table1)
133 A1 --- pf? [YN] Data affected by proton flux
filtering? (only for table2)
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Note (1): in line units.
Note (2): Averaged over the duration of the XMM-Newton observation.
Note (3): Expected from our extragalactic power-law model, Fexgal2-5.
This ratio was used as a measure of how much soft-proton contamination
remained in the spectrum after the lightcurve analysis described in
Section 3.1
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- DS [1-69] Dataset number
4 I1 --- Obs [1-7] Observation number within the dataset
6- 15 I010 --- XMM XMM observation identification
17- 23 F7.3 deg GLON Galactic longitude
25- 31 F7.3 deg GLAT Galactic latitude
33- 37 F5.2 --- IOVII0 OVII intensity without proton flux
filtering (1)
39- 43 F5.2 --- e_IOVII0 Lower bound of 68% confidence interval
for IOVII0 (1)
45- 49 F5.2 --- E_IOVII0 Upper bound of 68% confidence interval
for IOVII0 (1)
51- 54 F4.2 --- IOVIII0 OVIII intensity without proton flux
filtering (1)
56- 59 F4.2 --- e_IOVIII0 Lower bound of 68% confidence interval
for IOVIII0 (1)
61- 64 F4.2 --- E_IOVIII0 Upper bound of 68% confidence interval
for IOVIII0 (1)
66- 70 F5.2 --- IOVII1 ? O VII intensity with proton flux
filtering (1)
72- 76 F5.2 --- e_IOVII1 ? Lower bound of 68% confidence interval
for IOVII1 (1)
78- 82 F5.2 --- E_IOVII1 ? Upper bound of 68% confidence interval
for IOVII1 (1)
84- 87 F4.2 --- IOVIII1 ? O VIII intensity with proton flux
filtering (1)
89- 92 F4.2 --- e_IOVIII1 ? Lower bound of 68% confidence interval
for IOVIII1 (1)
94- 97 F4.2 --- E_IOVIII1 ? Upper bound of 68% confidence interval
for IOVIII1 (1)
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Note (1): in line units.
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History:
From electronic version of the journal
References:
Henley & Shelton Paper II. 2012ApJS..202...14H 2012ApJS..202...14H Cat. J/ApJS/202/14
Henley & Shelton Paper III. 2013ApJ...773...92H 2013ApJ...773...92H Cat. J/ApJ/773/92
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 25-May-2010