Blazar PKS 1424-414 (z=1.522) brightening
Posted: Wed Jul 27, 2022 8:54 am
Hi All
There was a recent ATel #15525 reporting a brightening of this very distant object up to a mag of R=13.4
I tried to take a spectrum of it using my LISA. It is pretty dim but I could certainly obtained a spectrum. It seems pretty flat but because of the high redshift it is difficult for me to determine even vague lines.
Certainly a z=1.522, this is the furthest out object I have been able to take a spectrum of.
Terry
Posted: Within the last 24 hours
==============================================================================
ATEL #15525 ATEL #15525
Title: Bright optical/GeV-ray flares in Blazars PKS 1424-418 and PKS
1406-076
Author: F. Jankowsky, S. J. Wagner, F. Ait-Benkhali (LSW Heidelberg)
Queries: swagner@lsw.uni-heidelberg.de
Posted: 23 Jul 2022; 23:10 UT
Subjects:Optical, Gamma Ray, >GeV, AGN, Blazar, Quasar
Optical observations of the PKS 1424-418 (z=1.522, White et al., ApJ, 327,
561 (1988)) with the Automatic Telescope for Optical Monitoring (ATOM)
in Namibia reveal this Blazar in a bright optical state. Preliminary analysis
of measurements performed on July 23 2022 (MJD 59783.8) show a peak R
magnitude of 13.4 with 0.1 mag variations within one hour. This is 4.6
magnitudes brighter than the
lowest flux measured during the last 15 years. PKS 1424-418 underwent a
steady increase in brightness by 1.2 magnitudes since July 15, 2022 (MJD
59775.2). The optical flare is 0.9 mag brighter than an earlier outburst
observed in May 2010, with a coincident GeV Gamma-ray flare (ATEL #2613,
Buson et al., AA 569, A40 (2014)).
The flare observed in the optical band coincides with an increase of gamma-ray
flux recorded in the 100 MeV - 500 GeV band with the Fermi-LAT instrument
reaching a level of 3.5 10<sup>-6</sup> cm<sup>-2 </sup> s<sup>-1</sup>
on July 22 2022, exceeding the flux of the 2013 flare which has been
the brightest flare in the LAT band so far.
Optical observations of the Blazar PKS 1406-076 (z=1.494, Wilkes et al.,
PASA, 5, 2 (1983)) with ATOM show this Blazar in a bright optical state.
Preliminary analysis of measurements performed on July 23 2022 (MJD 59783.8)
show a peak R magnitude of 16.2. This is 3 magnitudes brighter than the
lowest flux measured during the last 15 years. PKS 1406-076 underwent a
steady increase in brightness by 1.7 magnitudes since May 24, 2022 (MJD
59723.8). This is the brightest flare recorded with ATOM during the past
15 years.
Further multi-frequency observations of these outbursts are encouraged.
ATOM is a 75cm optical telescope located at the H.E.S.S. site in Namibia.
Fermi-LAT fluxes are available also on the public LAT light curve page.
There was a recent ATel #15525 reporting a brightening of this very distant object up to a mag of R=13.4
I tried to take a spectrum of it using my LISA. It is pretty dim but I could certainly obtained a spectrum. It seems pretty flat but because of the high redshift it is difficult for me to determine even vague lines.
Certainly a z=1.522, this is the furthest out object I have been able to take a spectrum of.
Terry
- PKS1424 418pointing_small.png (545.46 KiB) Viewed 2320 times
Posted: Within the last 24 hours
==============================================================================
ATEL #15525 ATEL #15525
Title: Bright optical/GeV-ray flares in Blazars PKS 1424-418 and PKS
1406-076
Author: F. Jankowsky, S. J. Wagner, F. Ait-Benkhali (LSW Heidelberg)
Queries: swagner@lsw.uni-heidelberg.de
Posted: 23 Jul 2022; 23:10 UT
Subjects:Optical, Gamma Ray, >GeV, AGN, Blazar, Quasar
Optical observations of the PKS 1424-418 (z=1.522, White et al., ApJ, 327,
561 (1988)) with the Automatic Telescope for Optical Monitoring (ATOM)
in Namibia reveal this Blazar in a bright optical state. Preliminary analysis
of measurements performed on July 23 2022 (MJD 59783.8) show a peak R
magnitude of 13.4 with 0.1 mag variations within one hour. This is 4.6
magnitudes brighter than the
lowest flux measured during the last 15 years. PKS 1424-418 underwent a
steady increase in brightness by 1.2 magnitudes since July 15, 2022 (MJD
59775.2). The optical flare is 0.9 mag brighter than an earlier outburst
observed in May 2010, with a coincident GeV Gamma-ray flare (ATEL #2613,
Buson et al., AA 569, A40 (2014)).
The flare observed in the optical band coincides with an increase of gamma-ray
flux recorded in the 100 MeV - 500 GeV band with the Fermi-LAT instrument
reaching a level of 3.5 10<sup>-6</sup> cm<sup>-2 </sup> s<sup>-1</sup>
on July 22 2022, exceeding the flux of the 2013 flare which has been
the brightest flare in the LAT band so far.
Optical observations of the Blazar PKS 1406-076 (z=1.494, Wilkes et al.,
PASA, 5, 2 (1983)) with ATOM show this Blazar in a bright optical state.
Preliminary analysis of measurements performed on July 23 2022 (MJD 59783.8)
show a peak R magnitude of 16.2. This is 3 magnitudes brighter than the
lowest flux measured during the last 15 years. PKS 1406-076 underwent a
steady increase in brightness by 1.7 magnitudes since May 24, 2022 (MJD
59723.8). This is the brightest flare recorded with ATOM during the past
15 years.
Further multi-frequency observations of these outbursts are encouraged.
ATOM is a 75cm optical telescope located at the H.E.S.S. site in Namibia.
Fermi-LAT fluxes are available also on the public LAT light curve page.