LONG-TERM MONITORING OF THE HARD X-RAY/GAMMA-RAY EMISSION FROM GALACTIC BLACK HOLES WITH BATSE

Radiocesium monitoring in sediments and river water has been conducted along five rivers in Minami-Soma City during 2012–2016 to clarify the temporal changes of radiocesium contamination in these rivers. Sampling has been performed annually under normal flow conditions. Sediment and river water samples were collected from four or five sampling sites along each river. Gamma-ray measurements of sediments were performed using a low-background Ge detector and unfiltered river water was utilized to determine radiocesium concentration using a well-type Ge detector. The 137Cs concentration in sediments was highest at upstream sites and slowly decreased to downstream sites for all rivers reflecting the high radioactive contamination in the upstream area. Temporal decrease of the 137Cs concentration was observed in sediments and river water for each river. The effective half-lives were 1.3–2.1 y for sediments, and 0.9–2.1 y for river water from rivers with upstream dams. On the undammed river, the effective half-lives were 4.7 y and 3.7 y for sediment and river water, respectively. Much longer effective-half-lives might reflect the direct transfer of radiocesium from forests and plains to the river. The 137Cs concentration in riverbed was low in downstream areas, however, accumulation of 137Cs over the floodplain was observed. Rapid decrease of 137Cs contamination through rivers will put residents at ease, but high accumulation of radiocesium over floodplains should be noted for future river decontamination.

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Thermal hard X-ray and gamma ray emission of disk-accreting black holes

10.1063/1.44306 ◽

1993 ◽

Author(s):

Edison P. Liang

Keyword(s):

Black Holes ◽

Gamma Ray ◽

X Ray ◽

Gamma Ray Emission

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Global One-armed Oscillations in the Be/X-ray Binary LS I +61° 235/RX J0146.9+6121

International Astronomical Union Colloquium ◽

10.1017/s0252921100056827 ◽

2000 ◽

Vol 175 ◽

pp. 719-722

Author(s):

P. Reig ◽

I. Negueruela ◽

M.J. Coe ◽

J. Fabregat ◽

A.E. Tarasov

Keyword(s):

Density Perturbation ◽

Infrared Emission ◽

High Density ◽

X Ray ◽

Oscillation Model ◽

Be Star ◽

Long Term Monitoring ◽

Term Monitoring

AbstractWe present results of our long-term monitoring of LS I +61° 235 in the optical and infrared bands. This Be/X-ray binary exhibits V/R variability in the Hα line, which can be explained in the framework of the Global One-armed Oscillation model: a high density perturbation moves around inside the circumstellar disc of the Be star. The V>R and V<R peaks occur when the perturbation moves towards and away from the observer, respectively. In this work we show that the perturbation also affects the He I λ6678Å and Paschen lines. We also report on a correlation between the infrared emission and the V/R variability.

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The Extremes of AGN Variability

Proceedings of the International Astronomical Union ◽

10.1017/s1743921317001648 ◽

2016 ◽

Vol 12 (S324) ◽

pp. 168-171 ◽

Cited By ~ 3

Author(s):

S. Komossa ◽

D. Grupe ◽

N. Schartel ◽

L. Gallo ◽

J. L. Gomez ◽

...

Keyword(s):

Active Galactic Nuclei ◽

Galactic Nuclei ◽

X Ray ◽

Accretion Flow ◽

Multi Wavelength ◽

Long Term Monitoring ◽

Term Monitoring ◽

Spectral States ◽

Ongoing Monitoring

AbstractWe present results from our ongoing monitoring programs aimed at identifying and understanding Active Galactic Nuclei (AGN) in extreme flux and spectral states. Observations of AGN in extreme states can reveal the nature of the inner accretion flow, the physics of matter under strong gravity, and they provide insight on the properties of ionized absorbers and outflows launched near supermassive black holes (SMBHs). We present new results from our long-term monitoring of IC 3599, WPVS007, and Mrk 335, multi-wavelength follow-ups of the newly identified changing-look AGN HE 1136–2304, and UV–X-ray follow-ups of the binary SMBH candidate OJ 287 after its 2015 optical maximum, now in a new optical-X-ray–high-state.

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Discovery of a retrogradely rotating neutron star in the X-ray pulsar GX 301–2

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa906 ◽

2020 ◽

Vol 494 (2) ◽

pp. 2178-2182

Author(s):

Juhani Mönkkönen ◽

Victor Doroshenko ◽

Sergey S Tsygankov ◽

Armin Nabizadeh ◽

Pavel Abolmasov ◽

...

Keyword(s):

Neutron Star ◽

Gamma Ray ◽

Orbital Motion ◽

X Ray ◽

Spin Evolution ◽

Ultimate Result ◽

Term Monitoring ◽

Direction Opposite ◽

Principal Possibility

ABSTRACT We report on the analysis of the spin evolution of a slow X-ray pulsar GX 301–2 along the orbit using long-term monitoring by Fermi/Gamma-ray Burst Monitor. Based on the observationally confirmed accretion scenario and an analytical model for the accretion of angular momentum, we demonstrate that in this system, the neutron star spins retrogradely, that is, in a direction opposite to the orbital motion. This first-of-a-kind discovery of such a system proves the principal possibility of retrograde rotation in accreting systems with suitable accretion torque, and might have profound consequences for our understanding of the spin evolution of X-ray pulsars, estimates of their initial spin periods, and the ultimate result of their evolution.

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Long-term monitoring of the archetype Seyfert galaxy MCG-6-30-15: X-ray, optical and near-IR variability of the corona, disc and torus

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stv1945 ◽

2015 ◽

Vol 454 (1) ◽

pp. 368-379 ◽

Cited By ~ 25

Author(s):

P. Lira ◽

P. Arévalo ◽

P. Uttley ◽

I. M. M. McHardy ◽

L. Videla

Keyword(s):

Seyfert Galaxy ◽

X Ray ◽

Near Ir ◽

Long Term Monitoring ◽

Term Monitoring

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W. Röpke. Treatment of congenital clubfoot. (Arch. F. Klin. Chir. 1936, 186, 606-609)

Kazan medical journal ◽

10.17816/kazmj75552 ◽

1937 ◽

Vol 33 (7) ◽

pp. 940-940

Author(s):

B. Ivanov

Keyword(s):

Growth Period ◽

Congenital Clubfoot ◽

Plantar Aponeurosis ◽

X Ray ◽

Long Term Monitoring ◽

Muscle Groups ◽

Term Monitoring ◽

Vigorous Treatment

Based on his own observations a. believes that the treatment of congenital clubfoot should begin immediately after childbirth and consist of elastic manual redressing and independent active exercises of certain muscle groups. With strong resistance from the soft parts, the production of tenotomy and especially excision of the plantar aponeurosis is indicated. Violent and violent redress should be avoided; with old clubfoot and clubfoot in adults, when all attempts at plastic redressing are unsuccessful, surgery is indicated on the skeleton of the foot in the form of a wedge-shaped osteotomy, connected, if necessary, with intervention on the soft parts. Long-term monitoring is necessary throughout the entire growth period, even in successfully treated children; At the same time, X-ray observation of the centers of ossification is of great importance as an indicator of the result of treatment, since insufficient ossification, along with other moments, sooner or later can lead to relapses requiring long-term and vigorous treatment.

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