Optical Short-Term Variability in the X-Ray-Selected BL LAC Object IE 0317+186 and the Radio-Selected BL LAC Object ON231

In order to compare X-ray-selected BL Lac objects with radio-selected BL Lac objects, we have carried out optical monitoring of some of these objects for about three years at Yunnan Observatory in China. All observations have been made with a CCD-image system at the f/13.3 Cassegrain focus of the 102-cm RCC telescope. The CCD-image system was developed by Ye et al. in Kitt Peak National Observatory of USA (Ye et al., 1985). The filters used were as follows: B-GG385(2mm)+BG12(1mm)+BG18(1mm), V-GG495(2mm)+BG18(2mm). After observing many times, more complete light curves have obtained for the X-ray-selected BL Lac object IE 0317+186 and the radio-selected BL Lac object ON 231, respectively(Fig 1 and Fig 2). Fig 1 shows that IE 0317+186 has a characteristic timescale of about 4.5hours with an amplitudes of ΔV≃0.65 mag. Fig 2 indicates that a timescale of short-term variability in ON 231 is about 70 min with an amplitudes of ΔB≃0.8 mag.

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Correlated X-ray/UV/optical emission and short-term variability in a Seyfert 1 galaxy NGC 4593

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stx3103 ◽

2017 ◽

Vol 474 (4) ◽

pp. 5351-5362 ◽

Cited By ~ 10

Author(s):

Main Pal ◽

Sachindra Naik

Keyword(s):

Optical Emission ◽

Short Term ◽

X Ray ◽

Short Term Variability

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XMM-Newton observations of eleven intermediate polars and possible candidates

Astronomy and Astrophysics ◽

10.1051/0004-6361/202038038 ◽

2020 ◽

Vol 639 ◽

pp. A17

Author(s):

H. Worpel ◽

A. D. Schwope ◽

I. Traulsen ◽

K. Mukai ◽

S. Ok

Keyword(s):

Optical Data ◽

Plasma Emission ◽

Short Term ◽

X Ray ◽

Hot Plasma ◽

Intermediate Polars ◽

Orbital Periods ◽

Firm Evidence ◽

Short Term Variability

Aims. We aim to identify new intermediate polars (IPs) in XMM-Newton observations from a list of promising candidates. By selecting targets not previously known to be X-ray bright, we aim to uncover evidence for an X-ray underluminous IP subpopulation. Methods. We performed period searches on the XMM-Newton X-ray and optical data of our targets to seek both the spin and orbital periods, which differ in IPs. We also investigated the X-ray spectra to find the hot plasma emission shown by these objects. With archival Swift data we coarsely investigated the long-term X-ray variability, and with archival optical data from a variety of catalogues, we compared the optical to X-ray luminosity to identify X-ray faint objects. This paper presents the first XMM-Newton observation of the prototype IP, DQ Her. Results. We find firm evidence for HZ Pup, V349 Aqr, and IGR J18151-1052 being IPs, with likely white dwarf spin periods of 1552, 390, and 390 s, respectively. The former two have luminosities typical of IPs, and the latter is strongly absorbed and with unknown distance. GI Mon and V1084 Her are apparently non-magnetic CVs with interesting short-term variability unrelated to WD spin. V533 Her is probably a magnetic CV and remains a good IP candidate, while V1039 Cen is possibly a polar. The remaining candidates were too faint to allow for any firm conclusions.

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Short Term Variability of Pulsations in the X-ray Flux from Cygnus X1

Nature ◽

10.1038/233468a0 ◽

1971 ◽

Vol 233 (5320) ◽

pp. 468-469 ◽

Cited By ~ 3

Author(s):

A. M. CRUISE ◽

A. C. NEWTON ◽

C. E. CHAPMAN

Keyword(s):

Short Term ◽

X Ray ◽

Short Term Variability

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Non-radial pulsations in the Be/X binaries 4U 0115+63 and SAX J2103.5+4545

Proceedings of the International Astronomical Union ◽

10.1017/s1743921311011197 ◽

2010 ◽

Vol 6 (S272) ◽

pp. 505-506

Author(s):

Juan Gutiérrez-Soto ◽

Pablo Reig ◽

Juan Fabregat ◽

Lester Fox-Machado

Keyword(s):

Complex Systems ◽

Magellanic Clouds ◽

Short Term ◽

New Approach ◽

X Ray ◽

Preliminary Results ◽

Stellar Pulsations ◽

X Ray Binaries ◽

Radial Pulsations ◽

Short Term Variability

AbstractThe discovery of non-radial pulsations (NRP) in the Be/X binaries of the Magellanic Clouds (MC, eg. Fabrycky 2005, Coe et al. 2005, Schmidtke & Cowley 2005) provided a new approach to understand these complex systems, and, at the same time, favoured the synergy between two different fields: stellar pulsations and X-ray binaries. This breakthrough was possible thanks to the MACHO and OGLE surveys. However, in our Galaxy, only two Be/X have been reported to show NRP: GRO J2058+42 (Kiziloglu et al. 2007) and LSI+61 235 (Sarty et al. 2009). Our objective is to study the short-term variability of Galactic Be/X binaries, compare them to the Be/X of the MC and to the isolated Galactic Be observed with corot and kepler. We present preliminary results of two Be/X stars, namely 4U 0115+63 and SAX J2103.5+4545 showing multiperiodicity and periodicity respectively, most probable produced by NRP.

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BL Lac: Strong Short-term Variability

Nature Physical Science ◽

10.1038/physci241157a0 ◽

1973 ◽

Vol 241 (113) ◽

pp. 157-158 ◽

Cited By ~ 7

Author(s):

DONNA WEISTROP

Keyword(s):

Short Term ◽

Bl Lac ◽

Short Term Variability

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MAGIC detection of short-term variability of the high-peaked BL Lac object 1ES 0806+524

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stv895 ◽

2015 ◽

Vol 451 (1) ◽

pp. 739-750 ◽

Cited By ~ 13

Author(s):

J. Aleksić ◽

S. Ansoldi ◽

L. A. Antonelli ◽

P. Antoranz ◽

A. Babic ◽

...

Keyword(s):

Short Term ◽

Bl Lac ◽

Short Term Variability

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GCT-08. PROTON BEAM RADIOTHERAPY FOR PEDIATRIC AND YOUNG-ADULT PATIENTS WITH INTRACRANIAL GERM CELL TUMOR

Neuro-Oncology ◽

10.1093/neuonc/noaa222.229 ◽

2020 ◽

Vol 22 (Supplement_3) ◽

pp. iii329-iii329

Author(s):

Minako Sugiyama ◽

Takayuki Hashimoto ◽

Takashi Mori ◽

Kazuya Hara ◽

Yukayo Terashita ◽

...

Keyword(s):

Young Adult ◽

Adverse Events ◽

Germ Cell ◽

Cell Count ◽

Proton Beam ◽

Adult Patients ◽

Short Term ◽

Intracranial Germ Cell Tumor ◽

X Ray ◽

Proton Beam Radiotherapy

Abstract BACKGROUND To reduce treatment-related adverse events in pediatric and young-adult patients with brain tumors, proton beam radiotherapy (PBT) has recently been performed instead of conventional X-ray radiotherapy. However, whether PBT is as effective as X-ray radiotherapy has not been sufficiently investigated, especially in patients receiving whole-ventricular irradiation. METHODS We report a retrospective observation of 15 patients with intracranial germ cell tumors (GCT), who received PBT at our institution from April 2014 to September 2019. We evaluated their clinical course, short-term adverse events, and prognosis. RESULTS/ CONCLUSION Fifteen patients (9 males and 6 females; median age 13 years) who received PBT following induction chemotherapy were analyzed. Nine patients received 23.4–27.0 GyE of whole-ventricular irradiation due to GCT in the pituitary gland, pineal body, or hypothalamic area. Three patients received 23.4 GyE of whole-brain irradiation: one of them had boost irradiation for basal ganglia. Three patients received 30.6 GyE of craniospinal irradiation (CSI). Six of the 15 patients experienced nausea (grade 2, according to the CTCAE version 4.0). Four patients, including two who received CSI, showed myelosuppression: decrease in white blood cell count, lymphocyte cell count, and neutrophil count (grade 3). No other severe short-term adverse events of >grade 2 was observed in any of the patients. At a median follow-up of 21 months (2-62 months) after irradiation. all patients are alive without recurrence. Our results may be encouraging and further investigations with a larger scale is warranted.

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A Comparison of the X-ray Spectra of Quasars and BL Lac Objects

Symposium - International Astronomical Union ◽

10.1017/s0074180900140811 ◽

1989 ◽

Vol 134 ◽

pp. 197-198

Author(s):

D. M. Worrall ◽

B. J. Wilkes

Keyword(s):

Power Law ◽

Radio Spectrum ◽

Spectral Indices ◽

Mean Power ◽

Bl Lac Objects ◽

X Ray ◽

Bl Lac ◽

Infrared Frequencies

Quasars with similar core-compact radio properties can be classified by their differences at optical and infrared frequencies. Their X-ray properties might be expected to be similar if the synchrotron self-Compton mechanism relates their radio and X-ray emission. We have compared the 0.2–3.5 keV mean power-law energy spectral indices, , for 4 quasar classes: 12 Highly Polarized QSOs (HPQs), 19 Flat Radio Spectrum, core-compact, low-polarization, QSOs (FRS QSOs), 24 radio-selected BL Lac objects, and 7 X-ray-selected BL Lac objects.

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