scholarly journals The Swift Bulge Survey: optical and near-IR follow-up featuring a likely symbiotic X-ray binary and a focused wind CV

2020 ◽  
Vol 492 (3) ◽  
pp. 4344-4360 ◽  
Author(s):  
A W Shaw ◽  
C O Heinke ◽  
T J Maccarone ◽  
G R Sivakoff ◽  
J Strader ◽  
...  
Keyword(s):  
White Dwarf ◽  
Near Infrared ◽  
Substantial Contribution ◽  
Galactic Centre ◽  
First Year ◽  
X Ray ◽  
Giant Stars ◽  
Near Ir ◽  
Star Binary

ABSTRACT The nature of very faint X-ray transients (VFXTs) – transient X-ray sources that peak at luminosities $L_X\lesssim 10^{36} {\rm \, erg \, s^{-1}}$ – is poorly understood. The faint and often short-lived outbursts make characterizing VFXTs and their multiwavelength counterparts difficult. In 2017 April we initiated the Swift Bulge Survey, a shallow X-ray survey of ∼16 square degrees around the Galactic centre with the Neil Gehrels Swift Observatory. The survey has been designed to detect new and known VFXTs, with follow-up programmes arranged to study their multiwavelength counterparts. Here we detail the optical and near-infrared follow-up of four sources detected in the first year of the Swift Bulge Survey. The known neutron star binary IGR J17445-2747 has a K4III donor, indicating a potential symbiotic X-ray binary nature and the first such source to show X-ray bursts. We also find one nearby M-dwarf (1SXPS J174215.0-291453) and one system without a clear near-IR counterpart (Swift J175233.9-290952). Finally, 3XMM J174417.2-293944 has a subgiant donor, an 8.7 d orbital period, and a likely white dwarf accretor; we argue that this is the first detection of a white dwarf accreting from a gravitationally focused wind. A key finding of our follow-up campaign is that binaries containing (sub)giant stars may make a substantial contribution to the VFXT population.

scholarly journals Characterization of conichalcite by SEM, FTIR, Raman and electronic reflectance spectroscopy

2005 ◽  
Vol 69 (2) ◽  
pp. 155-167 ◽  
Author(s):  
B. J. Reddy ◽  
R. L. Frost ◽  
W. N. Martens
Keyword(s):  
Near Infrared ◽  
Adsorbed Water ◽  
Reflectance Spectroscopy ◽  
Sem Images ◽  
X Ray ◽  
Near Ir ◽  
Ir Reflectance ◽  
Yavapai County ◽  
Ir Bands

AbstractThe mineral conichalcite from the western part of Bagdad mine, Bagdad, Eureka District, Yavapai County, Arizona, USA has been characterized by electronic, near-infrared (NIR), Raman and infrared (IR) spectroscopy. Scanning electron microscopy (SEM) images show that the mineral consists of bundles of fibres. Calculations based on the results of the energy dispersive X-ray analyses on a stoichiometric basis show the substitution of arsenate by 12 wt.% of phosphate in the mineral. Raman and IR bands are assigned in terms of the fundamental modes of AsO43− and PO43− molecules and are related to the mineral structure. Near-IR reflectance spectroscopy shows the presence of adsorbed water and hydroxyl units in the mineral. The Cu(II) coordination polyhedron in conichalcite can have at best pseudo-tetragonal geometry. The crystal field and tetragonal field parameters of the Cu(II) complex were calculated and found to agree well with the values reported for known tetragonal distortion octahedral complexes.

scholarly journals Identification of AGN in the XMM-Newton X-ray survey of the SMC

2019 ◽  
Vol 622 ◽  
pp. A29 ◽  
Author(s):  
Chandreyee Maitra ◽  
Frank Haberl ◽  
Valentin D. Ivanov ◽  
Maria-Rosa L. Cioni ◽  
Jacco Th. van Loon
Keyword(s):  
Near Infrared ◽  
Spectral Characteristics ◽  
Selection Criterion ◽  
Galactic Nuclei ◽  
Seyfert Galaxies ◽  
Mid Infrared ◽  
X Ray ◽  
Stellar Density ◽  
Narrow Emission

Context. Finding active galactic nuclei (AGN) behind the Magellanic Clouds (MCs) is difficult because of the high stellar density in these fields. Although the first AGN behind the Small Magellanic Cloud (SMC) were reported in the 1980s, it is only recently that the number of AGN known behind the SMC has increased by several orders of magnitude. Aims. The mid-infrared colour selection technique has proven to be an efficient means of identifying AGN, especially obscured sources. The X-ray regime is complementary in this regard and we use XMM-Newton observations to support the identification of AGN behind the SMC. Methods. We present a catalogue of AGN behind the SMC by correlating an updated X-ray point-source catalogue from our XMM-Newton survey of the SMC with previously identified AGN from the literature as well as a list of candidates obtained from the ALLWISE mid-infrared colour-selection criterion. We studied the properties of the sample with respect to their redshifts, luminosities, and X-ray spectral characteristics. We also identified the near-infrared counterpart of the sources from the VISTA observations. Results. The redshift and luminosity distributions of the sample (where known) indicate that we detect sources ranging from nearby Seyfert galaxies to distant and obscured quasars. The X-ray hardness ratios are compatible with those typically expected for AGN, and the VISTA colours and variability are also consistent with AGN. A positive correlation was observed between the integrated X-ray flux (0.2–12 keV) and the ALLWISE and VISTA magnitudes. We further present a sample of new candidate AGN and candidates for obscured AGN. Together these make an interesting subset for further follow-up studies. An initial spectroscopic follow-up of 6 out of the 81 new candidates showed that all six sources are active galaxies, although two have narrow emission lines.

scholarly journals Discovery and follow-up of the unusual nuclear transient OGLE17aaj

2019 ◽  
Vol 622 ◽  
pp. L2 ◽  
Author(s):  
M. Gromadzki ◽  
A. Hamanowicz ◽  
L. Wyrzykowski ◽  
K. V. Sokolovsky ◽  
M. Fraser ◽  
...  
Keyword(s):  
Light Curve ◽  
Black Body ◽  
Emission Lines ◽  
First Year ◽  
Tidal Disruption ◽  
Massive Black Holes ◽  
X Ray ◽  
New Type ◽  
Narrow Emission

Aims. We report on the discovery and follow-up of a peculiar transient, OGLE17aaj, which occurred in the nucleus of a weakly active galaxy. We investigate whether it can be interpreted as a new candidate for a tidal disruption event (TDE). Methods. We present the OGLE-IV light curve that covers the slow 60-day-long rise to maximum along with photometric, spectroscopic, and X-ray follow-up during the first year. Results. OGLE17aaj is a nuclear transient exhibiting some properties similar to previously found TDEs, including a long rise time, lack of colour-temperature evolution, and high black-body temperature. On the other hand, its narrow emission lines and slow post-peak evolution are different from previously observed TDEs. Its spectrum and light-curve evolution is similar to F01004-2237 and AT 2017bgt. Signatures of historical low-level nuclear variability suggest that OGLE17aaj may instead be related to a new type of accretion event in active super-massive black holes.

scholarly journals First-year follow-up of children with chronic nonbacterial osteomyelitis—an analysis of the German National Pediatric Rheumatologic Database from 2009 to 2018

2021 ◽  
Vol 23 (1) ◽  
Author(s):  
Christiane Reiser ◽  
Jens Klotsche ◽  
Anton Hospach ◽  
Rainer Berendes ◽  
Anja Schnabel ◽  
...  
Keyword(s):  
Disease Activity ◽  
Well Being ◽  
Whole Body ◽  
First Year ◽  
Cross Sectional ◽  
Daily Lives ◽  
X Ray ◽  
Mri Scans ◽  
Chronic Nonbacterial Osteomyelitis

Abstract Objective To assess the first-year features of patients with chronic nonbacterial osteomyelitis (CNO). Methods Patients with a diagnosis of CNO, disease duration of under 13 months, and first registration in the German National Pediatric Rheumatologic Database (NPRD) between 2009 and 2018 were included in this cross-sectional analysis. Results Of 774 documented patients, 62.8% were female, and all patients had a median age of 11 years. The most affected clinical sites were the tibia (29.7%), pelvis (28.0%), and femur (27.8%). HLA-B27 was positive in 48 of 314 analyzed patients (15.3%). In 406 patients, an X-ray was performed at the first visit; X-ray results showed osteosclerosis/−lysis in 34.0% and hyperostosis in 14.5% of the patients. MRI scans (focal and whole-body scans) were performed in 648 patients, and 81.5% showed a positive TIRM/STIR signal. A total of 84.7% of the patients were administered nonsteroidal anti-inflammatory drugs, 9.6% were administered oral glucocorticoids, 10.8% were administered disease-modifying anti-rheumatic drugs (DMARDs), and 6.1% were administered bisphosphonates. An evaluation of the patient’s questionnaire showed an overall well-being (NRS 0–10) of 2.0. The PedCNO disease “activity” score revealed a 70% improvement in variables in 43% of patients in the initial 1-year follow-up. Copresentation with diagnostic criteria of pediatric enthesitis-related arthritis was rare. Conclusion To our knowledge, the NPRD cohort seemed to be the largest cohort of children and adolescents suffering from CNO worldwide. Most patients were treated effectively with NSAIDs, and only a small group of patients was administered additional medication. The patient-defined measures of disease activity had a moderate impact on patients’ daily lives. Trial registration Not applicable.

scholarly journals A near-infrared survey for galactic Wolf-Rayet stars

2003 ◽  
Vol 212 ◽  
pp. 555-557
Author(s):  
Nicole L. Homeier ◽  
Robert D. Blum ◽  
Peter S. Conti ◽  
Anna Pasquali ◽  
Augusto Damineli
Keyword(s):  
Near Infrared ◽  
Galactic Plane ◽  
Galactic Disk ◽  
Infrared Observations ◽  
Near Ir ◽  
Relative Line ◽  
Set Up ◽  
Infrared Survey

Most of the Milky Way's evolved massive stellar population is hidden from view. We can attempt to remedy this situation with near-infrared observations, and in this paper we present our method for detecting Wolf-Rayet stars in highly extincted regions and apply it to the inner Galaxy. Using narrow-band filters at K-band wavelengths, we demonstrate how WR stars can be detected in regions where they are optically obscured. Candidates are selected for spectroscopic follow-up from our relative line and continuum photometry. The final results of applying this method with a near-IR survey in the Galactic plane will provide a more complete knowledge of the structure of the galactic disk, the role of metallicity in massive stellar evolution, and environments of massive star formation. In this paper we briefly describe the survey set-up and report on recent progress. We have discovered four emission-line objects in the inner Galaxy: two with nebular emission lines, and two new WR stars, both of late WC subtype.

Cost-Effectiveness of Chest X-Ray Follow-Up of Patients Treated for Seminoma of the Testis

1986 ◽  
Vol 72 (4) ◽  
pp. 405-408 ◽  
Author(s):  
Stefano Ciatto ◽  
Luca Cionini ◽  
Paolo Pacini
Keyword(s):  
Cost Effectiveness ◽  
Detection Rate ◽  
Primary Treatment ◽  
Stage I ◽  
First Year ◽  
Consecutive Series ◽  
X Ray ◽  
Chest X Ray ◽  
One Year

The authors report on a consecutive series of 253 cases of seminoma of the testis followed with periodic chest X-ray examinations from a minimum of three to a maximum of 27 years. The detection rate of asymptomatic intrathoracic metastases (ITM) was considered together with the costs of the follow-up procedure. Chest X-ray follow-up is not advisable beyond one year from primary treatment, since most (14 of 18) ITM occur in the first year, the detection rate of ITM beyond this date is too low (0.11% patients/year), and the related costs are too high (over $ 130,000 per ITM detected). Chest X-ray follow-up is questionable even in the first year after primary treatment for Stage I cases because of the low detection rate (1.38% patients/year) and the high costs (over $ 14,000 per ITM detected), whereas it appears to be opportune in Stages IIA and IIB.

What you see and what you get: combining near-infrared spectroscopy with powder diffraction

2017 ◽  
Vol 32 (S2) ◽  
pp. S3-S8
Author(s):  
Helen E. Maynard-Casely ◽  
Norman Booth ◽  
Leo Anderberg ◽  
Helen E.A. Brand ◽  
Daniel V. Cotton
Keyword(s):  
Remote Sensing ◽  
Infrared Spectroscopy ◽  
Near Infrared ◽  
Surface Composition ◽  
Planetary Surfaces ◽  
X Ray Diffraction ◽  
X Ray ◽  
Near Ir ◽  
Infra Red ◽  
Terrestrial Environments

Knowledge of the surface composition of planetary bodies comes from a number of sources; such as landers, remote sensing and meteorites. However, the bulk mapping of the composition of planetary surfaces has been undertaken by analysis of reflected sunlight and these data—principally collected in the near-infra-red (IR) region—are notoriously broad and ambiguous. Hence, if laboratory spectra could be tied to physical properties measurements, such as diffraction, this would substantially aid our understanding of processes occurring in these extra-terrestrial environments. This contribution presents the capability of collecting near-IR data at the same time as neutron and synchrotron X-ray diffraction in a range of conditions (low temperature, vacuum, and humidity variations) and highlights two examples where this capability could enhance our understanding of planetary surfaces.

scholarly journals Hybrid star HD 81817 accompanied by brown dwarf or substellar companion

2020 ◽  
Vol 638 ◽  
pp. A148
Author(s):  
Tae-Yang Bang ◽  
Byeong-Cheol Lee ◽  
Volker Perdelwitz ◽  
Gwanghui Jeong ◽  
Inwoo Han ◽  
...  
Keyword(s):  
White Dwarf ◽  
Semimajor Axis ◽  
Spectral Lines ◽  
Brown Dwarf ◽  
Hybrid Star ◽  
Echelle Spectrograph ◽  
X Ray ◽  
Surface Activities ◽  
Giant Stars ◽  
Hybrid Stars

HD 81817 is known as a hybrid star. Hybrid stars have both cool stellar wind properties and Ultraviolet (UV) or even X-ray emission features of highly ionized atoms in their spectra. A white dwarf companion has been suggested as the source of UV or X-ray features. HD 81817 has been observed since 2004 as a part of a radial velocity (RV) survey program to search for exoplanets around K giant stars using the Bohyunsan Observatory Echelle Spectrograph at the 1.8 m telescope of Bohyunsan Optical Astronomy Observatory in Korea. We obtained 85 RV measurements between 2004 and 2019 for HD 81817 and found two periodic RV variations. The amplitudes of RV variations are around 200 m s−1, which are significantly lower than that expected from a closely orbiting white dwarf companion. Photometric data and relevant spectral lines were also analyzed to help determine the origin of the periodic RV variations. We conclude that 627.4-day RV variations are caused by intrinsic stellar activities such as long-term pulsations or rotational modulations of surface activities based on Hα equivalent width variations of a similar period. On the other hand, 1047.1-day periodic RV variations are likely to be caused by a brown dwarf or substellar companion, which is corroborated by a recent Gaia proper motion anomaly for HD 81817. The Keplerian fit yields a minimum mass of 27.1 MJup, a semimajor axis of 3.3 AU, and an eccentricity of 0.17 for the stellar mass of 4.3 M⊙ for HD 81817. The inferred mass puts HD 81817 b in the brown dwarf desert.

scholarly journals Integrity of personal radiation protective equipment (PRPE): a 3-year longitudinal follow-up study

2021 ◽  
Vol 42 (Supplement_1) ◽  
Author(s):  
P.-J Kellens ◽  
A De Hauwere ◽  
S Peire ◽  
I Tournicourt ◽  
L Strubbe ◽  
...  
Keyword(s):  
Interquartile Range ◽  
First Year ◽  
Protective Equipment ◽  
X Ray ◽  
Funding Sources ◽  
Rejection Criterion ◽  
Minimize Radiation Exposure ◽  
Operator Dose ◽  
Integrity Analysis

Abstract Background Personal radiation protective equipment (PRPE) such as lead aprons, vests, skirts and thyroid shields minimize radiation exposure of operators using ionizing radiation. However, PRPE might be prone to cracks and tears in the attenuating layer of the garments which results in inadequate radiation protection and increased operator dose. Currently, there are no uniform guidelines regarding regular inspection and/or rejection criteria of PRPE. Purpose This study aims to investigate the prevalence, qualification and quantification of PRPE integrity during a longitudinal follow-up. Methods All PRPE of a large, general hospital was yearly evaluated in the period 2018–2020. The equipment was inspected on a tele-operated X-ray table and cracks and tears were qualified and quantified using an X-ray opaque ruler. Rejection criteria of Lambert & McKeon were applied to accept or reject further use of the PRPE. In brief, all pieces, except for thyroid shields, with a total defect area larger than 670mm2 are rejected. For tears, specifically at the position of the gonads, an extra rejection criterion of 15mm2 is defined. For thyroid shields, the rejection criterion is set to 11mm2. Results In the 3-year follow-up period, a total of 915 PRPE were evaluated. 43.3% of PRPE showed tears and 29.3% needed to be rejected based on the Lambert & McKeon criteria. More specifically, in 2018, 2019 and 2020, respectively, 17.4%, 16.9% and 21.2% were rejected. In the attached figure, typical examples of visualized defects are represented. The median tear area (interquartile range) was 12 (30) mm2. Remarkably, of 195 newly registered PRPE, 8.7% showed tears in the first year of use of which 88.2% needed to be rejected. In the latter case, the median tear area (interquartile range) was 40 (50) mm2. Information regarding purchase date and size is missing in respectively 45.5% and 50.7% of the cases. Additionally, 13.7% lacked information regarding lead equivalency. Conclusion PRPE are prone to tears and cracks. Up to 40% of PRPE showed tears and cracks resulting in nearly 20% rejections. Newly purchased PRPE are not guaranteed to remain free of cracks and tears in the first year of use. These results urge the importance for regular X-ray based integrity analysis of PRPE. FUNDunding Acknowledgement Type of funding sources: None.

scholarly journals Chandra localization and optical/near-infrared follow-up of Galactic X-ray sources

2010 ◽  
Vol 408 (3) ◽  
pp. 1866-1878 ◽  
Author(s):  
E. M. Ratti ◽  
C. G. Bassa ◽  
M. A. P. Torres ◽  
L. Kuiper ◽  
J. C. A. Miller-Jones ◽  
...  
Keyword(s):  
Near Infrared ◽  
X Ray
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