We study the variability of the quasar HS 1946+7658 on intra-night time scale based on both our own optical and archival X-ray data. We find the quasar non-variable during about 11 hours of optical monitoring. This is in accordance with the low intra-night variability duty cycle of radio-quiet quasars. Regarding the X-rays, we cannot make a firm conclusion about the quasar variability owing to the controversial results of the light curves statistical analysis. In addition, we calibrated Johnson-Cousins BVRI magnitudes of 7 field stars that are to be used as secondary standards.

1.
S.
Kaspi
,
W. N.
Brandt
,
D.
Maoz
,
H.
Netzer
,
D. P.
Schneider
, and
O.
Shemmer
,
ApJ
659
,
997
1007
(
2007
).
2.
X.-M.
Fan
and
D.
Tytler
,
ApJS
94
,
17
46
(
1994
).
3.
M.-P.
Véron-Cetty
and
P.
Véron
,
A&A
518
,
A10
(
2010
).
4.
J.
Bechtold
 et al,
AJ
108
,
759
765
(
1994
).
5.
H.-J.
Hagen
 et al,
A&A
253
,
L5
L8
(
1992
).
6.
B. M.
Mihov
,
R. S.
Bachev
,
A. A.
Strigachev
,
L. S.
Slavcheva
, and
G. T.
Petrov
, “
Photometric Monitoring of Selected Quasars: The Highly Luminous Quasar HS 1946+7658
”, in
Active Galactic Nuclei and Related Phenomena
,
IAU Symposium 194 Proceedings
, edited by
Y.
Terzian
,
E.
Khachikian
, and
D.
Weedman
(
San Francisco
:
Astronomical Society of the Pacific
,
1999
), pp.
175
176
.
7.
B. M.
Mihov
and
L. S.
Slavcheva-Mihova
,
BlgAJ
27
,
3
9
(
2017
).
8.
T.
Bonev
,
Publ. Astron. Obs. Belgrade
90
,
201
204
(
2010
).
9.
T.
Bonev
, “The 2-Meter Telescope of the National Astronomical Observatory Rozhen: Opportunities for GAIA-FUN-SSO”, in
Gaia Follow-up Network for Solar System Objects Proceedings
(
Observatoire de Paris
,
2010
), pp.
89
92
.
10.
B. M.
Mihov
and
L. S.
Slavcheva-Mihova
,
AN
329
,
418
425
(
2008
).
11.
M. K.
Tsvetkov
,
T. B.
Georgiev
,
B. P.
Bilkina
,
A. G.
Tsvetkova
, and
E. H.
Semkov
,
C. R.
Acad
.
Bulg. Sci.
40
,
9
12
(
1987
).
12.
E. H.
Semkov
and
A. S.
Mutafov
, “
Wide-Field Spectroscopy with 3.5 Degree Objective Prism and 50/70 cm Rozhen Schmidt Telescope
”, in
Wide-Field Spectroscopy
,
2nd conference of the Working Group of IAU Commission 9 on “Wide-Field Imaging
” Proceedings, edited by
E.
Kontizas
,
M.
Kontizas
,
D. H.
Morgan
, and
G. P.
Vettolani
(
Astrophysics and Space Science Library 212, Springer, Dordrecht
,
1997
), pp.
125
126
.
13.
A.
Kostov
, “Opportunities for Follow-Up Observations of Solar System Objects with 50/70 cm Schmidt Telescope of National Astronomical Observatory Rozhen, Bulgaria”, in
Gaia Follow-up Network for Solar System Objects Proceedings
(
Observatoire de Paris
,
2010
), pp.
137
141
.
14.
L. Zibecchiet
al
.,
MNRAS
467
,
340
352
(
2017
).
15.
R.
Joshi
,
H.
Chand
,
A. C.
Gupta
, and
P. J.
Wiita
,
MNRAS
412
,
2717
2728
(
2011
).
16.
R.
Bachev
,
A.
Strigachev
, and
E.
Semkov
,
MNRAS
358
,
774
780
(
2005
).
17.
T. J.
Turner
,
K.
Nandra
,
D.
Turcan
,
I. M.
George
, “
tartarus – An ASCA AGN database
”, in
X-RAY ASTRON-OMY: Stellar Endpoints, AGN, and the Diffuse X-ray Background
,
AIP Conference Proceedings 599
, edited by
N. E.
White
,
G.
Malaguti
, and
G. G.C.
Palumbo
(
Melville, NY
:
American Institute of Physics
,
2001
), pp.
991
994
.
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