J/A+A/538/A26 BL Lac objects beyond z=1.3 (Rau+, 2012)
BL Lacertae objects beyond redshift 1.3 - UV-to-NIR photometry and
photometric redshift for Fermi/LAT blazars.
Rau A., Schady P., Greiner J., Salvato M., Ajello M., Bottacini E.,
Gehrels N., Afonso P.M.J., Elliott J., Filgas R., Kann D.A., Klose S.,
Kruehler T., Nardini M., Nicuesa Guelbenzu A., Olivares E.F., Rossi A.,
Sudilovsky V., Updike A.C., Hartmann D.H.
<Astron. Astrophys., 538, A26 (2012)>
=2012A&A...538A..26R 2012A&A...538A..26R
ADC_Keywords: BL Lac objects ; Redshifts ; Photometry, SDSS ;
Photometry, infrared ; Photometry, ultraviolet
Keywords: galaxies: distances and redshifts - techniques: photometric -
BL Lacertae objects: general
Abstract:
Observations of the γ-ray sky with Fermi led to significant
advances towards understanding blazars, the most extreme class of
active galactic nuclei. A large fraction of the population detected
by Fermi is formed by BL Lacertae (BL Lac) objects, whose sample has
always suffered from a severe redshift incompleteness due to the
quasi-featureless optical spectra.
Our goal is to provide a significant increase of the number of
confirmed high-redshift BL Lac objects contained in the 2 LAC
Fermi/LAT catalog.
Description:
For 103 Fermi/LAT blazars, photometric redshifts using spectral energy
distribution fitting have been obtained. The photometry includes 13
broad-band filters from the far ultraviolet to the near-IR observed
with Swift/UVOT and the multi-channel imager GROND at the MPG/ESO 2.2m
telescope. Data have been taken quasi-simultaneously and the remaining
source-intrinsic variability has been corrected for.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 75 104 Target list
table2.dat 119 104 Swift/UVOT photometry
table3.dat 118 104 GROND photometry
table4.dat 128 104 SED fits and photometric redshift solutions
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See also:
J/ApJS/188/405 : Fermi-LAT first source catalog (1FGL) (Abdo+, 2010)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 24 A24 --- Name Name
25 A1 --- n_Name [*] * for Extended morphology
27- 30 A4 --- --- [2FGL]
31- 42 A12 --- 2FGL Fermi/LAT 2FGL name (JHHMM.s+DDMM)
44- 45 I2 h RAh ? Right ascension (J2000) (1)
47- 48 I2 min RAm ? Right ascension (J2000) (1)
50- 54 F5.2 s RAs ? Right ascension (J2000) (1)
56 A1 --- DE- Declination sign (J2000) (1)
57- 58 I2 deg DEd ? Declination (J2000) (1)
60- 61 I2 arcmin DEm ? Declination (J2000) (1)
63- 66 F4.1 arcsec DEs ? Declination (J2000) (1)
68- 70 F3.1 arcsec Offset ? Offset of counterpart location from those
given in Ackermann et al. (2012, ApJ accepted)
72- 75 F4.2 mag E(B-V) Galactic redenning, from Schlegel et al.
(1998ApJ...500..525S 1998ApJ...500..525S.
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Note (1): GROND coordinates of the optical counterpart with typical
uncertainties of 0.3" in both directions.
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 24 A24 --- Name Name
26- 35 A10 "YYYY-MM-DD" Uobs.date UT date of UVOT observation (2)
37- 41 A5 "h:m" Uobs.time UT date of UVOT observation (2)
43 A1 --- l_W2mag Limit flag on W2mag (3σ upper limit)
44- 48 F5.2 mag W2mag ? Swift UVOT UVW2 AB magnitude (193nm) (G1)
50- 53 F4.2 mag e_W2mag ? rms uncertainty on W2mag
55 A1 --- l_M2mag Limit flag on M2mag (3σ upper limit)
56- 60 F5.2 mag M2mag ? Swift UVOT UVM2 AB magnitude (225nm) (G1)
62- 65 F4.2 mag e_M2mag ? rms uncertainty on M2mag
67 A1 --- l_W1mag Limit flag on W1mag (3σ upper limit)
68- 72 F5.2 mag W1mag ? Swift UVOT UVW1 AB magnitude (260nm) (G1)
74- 77 F4.2 mag e_W1mag ? rms uncertainty on W1mag
79 A1 --- l_Umag Limit flag on Umag (3σ upper limit)
80- 84 F5.2 mag Umag ? Swift UVOT U AB magnitude (346nm) (G1)
86- 89 F4.2 mag e_Umag ? rms uncertainty on Umag
91 A1 --- l_Bmag Limit flag on Bmag (3σ upper limit)
92- 96 F5.2 mag Bmag ? Swift UVOT B AB magnitude (439nm) (G1)
98-101 F4.2 mag e_Bmag ? rms uncertainty on Bmag
103 A1 --- l_Vmag Limit flag on Vmag (3σ upper limit)
104-108 F5.2 mag Vmag ? Swift UVOT V AB magnitude (547nm) (G1)
110-113 F4.2 mag e_Vmag ? rms uncertainty on Vmag
115-119 F5.2 mag Dmag ? Variability-correction factor to be
applied to GROND photometry
(ΔmGR->UV, see text)
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Note (2): Approximate start time of UVW2 exposure.
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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- 24 A24 --- Name Name
26- 35 A10 "YYYY-MM-DD" Gobs.date UT date of GROND observation start
37- 41 A5 "h:m" Gobs.time UT date of GROND observation start
43- 47 F5.2 mag g'mag ? GROND g' AB magnitude (G1)
49- 52 F4.2 mag e_g'mag ? rms uncertainty on g'mag
54- 58 F5.2 mag r'mag ? GROND r' AB magnitude (G1)
60- 63 F4.2 mag e_r'mag ? rms uncertainty on r'mag
65- 69 F5.2 mag i'mag ? GROND i' AB magnitude (G1)
71- 74 F4.2 mag e_i'mag ? rms uncertainty on i'mag
76- 80 F5.2 mag z'mag ? GROND z' AB magnitude (G1)
82- 85 F4.2 mag e_z'mag ? rms uncertainty on z'mag
87- 91 F5.2 mag Jmag ? GROND J AB magnitude (G1)
93- 96 F4.2 mag e_Jmag ? rms uncertainty on Jmag
98-102 F5.2 mag Hmag ? GROND H AB magnitude (G1)
104-107 F4.2 mag e_Hmag ? rms uncertainty on Hmag
109-113 F5.2 mag Kmag ? GROND K AB magnitude (G1)
115-118 F4.2 mag e_Kmag ? rms uncertainty on Kmag
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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- 24 A24 --- Name Name
26 A1 --- l_zp Limit flag on zp
27- 30 F4.2 --- zp ?=- Best photometric redshift
32- 35 F4.2 --- E_zp ? Error on zp (upper value)
37- 40 F4.2 --- e_zp ? Error on zp (lower value)
42- 45 F4.2 --- zs ?=- Spectrosocpic or imaging redshift (3)
47- 50 F4.2 --- zp1 ?=- Power-law photometric redshift
52- 55 F4.2 --- E_zp1 ? Error on zp1 (upper value)
(90% confidence uncertainty)
57- 60 F4.2 --- e_zp1 ? Error on zp1 (lowed value)
(90% confidence uncertainty)
62- 66 F5.1 --- X21 ? Power-law χ2 value
68- 72 F5.1 --- Pz1 ? Power-law redshift probability density at
zp1±0.1(1+zp1)
74- 77 F4.2 --- beta1 ? Spectral slope β for power law model
of the form Fl∝l-β
79- 82 F4.2 --- zp2 ?=- Galaxy photometric redshift
84- 87 F4.2 --- E_zp2 ? Error on zp2 (upper value)
(90% confidence uncertainty)
89- 92 F4.2 --- e_zp2 ? Error on zp2 (lowed value)
(90% confidence uncertainty)
94- 98 F5.1 --- X22 ? Galaxy χ2 value
100-104 F5.1 --- Pz2 ? Galaxy Pz value
106-128 A23 --- Model ? Galaxy model (4)
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Note (3): from Ackermann et al. (2012, ApJ, accepted).
Note (4): Starburst/QSO hybrid templates with varying contributions of the
two components. Template names reflect the relative contribution of
the starburst (I22491_NN) and AGN (TQSO1_NN) models to the hybrid.
"pl" marks an additional power-law component at short wavelengths.
See Salvato et al. (2011ApJ...742...61S 2011ApJ...742...61S) for details on the templates.
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Global Notes:
Note (G1): Corrrected for Galactic foreground reddening.
Not corrected for variability.
Nomenclature note:
In original tables, BZB J2313+1444 is a misprint for BZU J2313+1444.
History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 29-Mar-2012