J/AJ/162/92 126 X-rays sources around the cepheid η Aql (Evans+, 2021)
X-rays in Cepheids: XMM-Newton observations of ηAql.
Evans N.R., Pillitteri I., Kervella P., Engle S., Guinan E., Gunther H.M.,
Wolk S., Neilson H., Marengo M., Matthews L.D., Moschou S., Drake J.J.,
Guzik J.A., Gallenne A., Merand A., Hocde V.
<Astron. J., 162, 92-92 (2021)>
=2021AJ....162...92E 2021AJ....162...92E (SIMBAD/NED BibCode)
ADC_Keywords: Stars, variable; Stars, giant; X-ray sources; Positional data;
Photometry, infrared; Photometry, VRI
Keywords: Cepheid variable stars
Abstract:
X-ray bursts have recently been discovered in the Cepheids δCep
and βDor modulated by the pulsation cycle. We have obtained an
observation of the Cepheid ηAql with the XMM-Newton satellite at
the phase of maximum radius; the phase at which there is a burst of
X-rays in δCep. No X-rays were seen from the Cepheid ηAql at
this phase, and the implications for Cepheid upper atmospheres are
discussed. We have also used the combination of X-ray sources, as well
as Gaia and 2MASS data, to search for a possible grouping around the
young intermediate mass Cepheid. No indication of such a group was
found.
Description:
ηAql was observed by the XMM-Newton for 75ks on 2019 May 12 from
JD:2458615.584 to JD:2458616.452 (OBSID=0840510201).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 64 126 XMM-Newton sources in the image around ηAql
table3.dat 96 37 2MASS counterparts to XMM-Newton sources
table4.dat 118 53 Gaia counterparts to XMM-Newton sources
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See also:
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
I/337 : Gaia DR1 (Gaia Collaboration, 2016)
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
J/AJ/145/143 : XMM observations of α Per (Pillitteri+, 2013)
J/MNRAS/434/2238 : Cepheids in open clusters (Anderson+, 2013)
J/A+A/584/A80 : Pulsation model data for delta Cep and eta Aql (Merand+, 2015)
J/ApJ/813/29 : Classical and type II Cepheids IR excesses (Schmidt, 2015)
J/MNRAS/459/1170 : Coulour-Period relation for Cepheids (Scowcroft+, 2016)
J/A+A/623/A117 : Galactic Cepheids & RR Lyrae multiplicity II (Kervella+, 2019)
J/A+A/635/A33 : Galactic classical Cepheids Per-Lbol-Rad (Groenewegen, 2020)
J/AJ/159/121 : V-band light curve & RVs of the Cepheid V473Lyr (Evans+, 2020)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Seq [1/126] XMM/Newton Sequential source identifier
5- 13 F9.5 deg RAdeg [297/299] Right Ascension (J2000)
15- 21 F7.5 deg DEdeg [0.76/1.24] Declination (J2000)
23- 25 F3.1 arcsec PosErr [1/8.1] Positional uncertainty
27- 31 F5.2 arcmin Offaxis [0.69/15.8] Arcminutes off-axis
33- 38 F6.1 --- sigmabkg [4.8/3153] Significance, σbkg
40- 47 F8.2 ct/ks Rate [0.15/58000] Rate
49- 57 F9.3 ct/ks e_Rate [0.03/38000] Uncertainty in Rate
59- 64 F6.2 ks Texp [16.8/207] Exposure time
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Seq [11/125] XMM/Newton Sequential source identifier
5- 14 F10.6 deg RAdeg [297/299] Right Ascension (J2000)
16- 23 F8.6 deg DEdeg [0.86/1.24] Declination (J2000)
25- 40 A16 --- 2MASS 2MASS identifier
42- 48 F7.4 mag Jmag [7.35/16.8] 2MASS J-band magnitude
50- 55 F6.4 mag e_Jmag [0.02/0.2]? Uncertainty in Jmag
57- 63 F7.4 mag Hmag [6.86/16.2] 2MASS H-band magnitude
65- 70 F6.4 mag e_Hmag [0.02/0.3] Uncertainty in Hmag
72- 78 F7.4 mag Ksmag [6.67/15.9] 2MASS Ks-band magnitude
80- 85 F6.4 mag e_Ksmag [0.01/0.3]? Uncertainty in Ksmag
87- 89 A3 --- Qual 2MASS Quality flag
91- 96 F6.4 arcsec Sep [0.06/4.57] Separation
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 15 F15.11 deg RAdeg [297/299] Right Ascension (J2000)
17- 29 F13.11 deg DEdeg [0.76/1.22] Declination (J2000)
31- 34 F4.2 arcsec Sep [0.04/1] Separation, XMM to Gaia source
36- 54 I19 --- Gaia Gaia DR2 object identifier
56- 58 I3 --- Seq [4/126] XMM/Newton Sequential source identifier
60- 66 F7.4 mas plx [-2.14/10.8] Gaia DR2 Parallax
68- 73 F6.4 mas e_plx [0.02/1.7] Uncertainty in Par
75- 81 F7.4 mag Gmag [13/20.9] Gaia DR2 G-band magnitude
83- 88 F6.4 mag e_Gmag [0.0007/0.02] Uncertainty in Gmag
90- 96 F7.4 mag BPmag [13.5/21.3]? Gaia DR2 BP-band magnitude
98-103 F6.4 mag e_BPmag [0.005/0.3]? Uncertainty in BPmag
105-111 F7.4 mag RPmag [12/20.4]? Gaia DR2 RP-band magnitude
113-118 F6.4 mag e_RPmag [0.001/0.2]? Uncertainty in RPmag
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History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 25-Nov-2021