2012A&A...538A.125Z


C.D.S. - SIMBAD4 rel 1.7 - 2021.03.04CET10:10:44

2012A&A...538A.125Z - Astronomy and Astrophysics, volume 538A, 125-125 (2012/2-1)

Intra-night optical multiband variability of BL Lacertae during the 2011 outburst.

ZHAI M. and WEI J.Y.

Abstract (from CDS):

We present our optical multiband (B and R) observations of BL Lacertae, which were acquired over 20 nights from May 26 to August 3, 2011, and analyse our data to study the optical emission variability properties of BL Lac. The simultaneous photometric observations were carried out using the 0.8m Tsinghua-NAOC Telescope (TNT) at the Xinglong Observatory of National Astronomical Observatories, Chinese Academy of Sciences (NAOC). TNT is equipped with the Princeton Instrument CCD and standard Johnson-Cousin UBVRI filters. Exposure times were well chosen to make a good compromise between high precision and high temporal density. A multipeak outburst was observed in 2011 observing season. The brightest magnitudes for BL Lac during our observations were B=14.48mag and R=12.89mag at JD=2455709.2810 (May 27). One of the most rapid variations was detected on July 9, when a flux increase of about 0.34mag occurred over 2.8h. In general, both the amplitude of variability and the variation rate are higher at the shorter wavelength. A colour analysis shows that the colour variability processes are apparently complicated. A bluer-when-brighter trend was detected during the outburst. These trends may be the interactive contribution from a ``mildly-chromatic'' component and a ``strongly-chromatic'' one. Meanwhile, intra-night variability in B and R bands was found to be correlated, without any time delay exceeding 2.5-min.

Abstract Copyright:

Journal keyword(s): galaxies: jets - quasars: general - galaxies: active - quasars: individual: BL Lacertae

Simbad objects: 2

goto Full paper

goto View the reference in ADS

Number of rows : 2

N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2021
#notes
1 NAME BL Lac BLL 22 02 43.2913773726 +42 16 39.978417860   15.66 14.72     ~ 2037 1
2 3C 454.3 Bla 22 53 57.74798 +16 08 53.5611   16.57 16.10 15.22   ~ 2557 2

    Equat.    Gal    SGal    Ecl

To bookmark this query, right click on this link: simbad:objects in 2012A&A...538A.125Z and select 'bookmark this link' or equivalent in the popup menu


2021.03.04-10:10:44

© Université de Strasbourg/CNRS

    • Contact