scholarly journals Survey of OH Masers at 1665 MHz. II. Galactic Longitude 340o to the Galactic Centre

1983 ◽  
Vol 36 (3) ◽  
pp. 361 ◽  
Author(s):  
JL Caswell ◽  
RF Haynes
Keyword(s):  
Ground State ◽  
Galactic Plane ◽  
Line Emission ◽  
State Transitions ◽  
Galactic Centre ◽  
Emission Sources ◽  
Type I ◽  
Type Ii ◽  
Formation Type ◽  
Galactic Longitude

The galactic plane from longitude 340� through the galactic centre to longitude + 2� has been searched for OH on the 1665 MHz transition. Forty-nine OH maser emission sources were detected and these have now been studied on all four OH ground-state transitions. Most of the masers are associated with regions of star formation (type I) while three may be examples of late-type stars (type II OH/IR) with unusually strong main-line emission

scholarly journals A Multi-Wavelength View of the XMM-Newton Galactic Plane

2014 ◽  
Vol 1 (1) ◽  
pp. 123-126
Author(s):  
Ada Nebot Gómez-Morán ◽  
Christian Motch
Keyword(s):  
Surface Density ◽  
Binary Systems ◽  
Galactic Plane ◽  
Galactic Centre ◽  
Galactic Latitude ◽  
X Ray ◽  
Model Predictions ◽  
Science Centre ◽  
Multi Wavelength ◽  
Galactic Longitude

We present an X-ray survey of the Galactic Plane conducted by the Survey Science Centre of the XMM-Newton satellite. The survey contains more than 1300 X-ray detections at low and intermediate Galactic latitudes and covering 4 deg<sup>2</sup> well spread in Galactic longitude. From a multi-wavelength analysis, using optical spectra and helped by optical and infrared photometry we identify and classify about a fourth of the sources. The observed surface density of soft X-ray (&lt;2 keV) sources decreases with Galactic latitude and although compatible with model predictions at first glance, presents an excess of stars, likely due to giants in binary systems. In the hard band (&gt;2 keV) the surface density of sources presents an excess with respect to the expected extragalactic contribution. This excess highly concentrates towards the direction of the Galactic Centre and is compatible with previous results from Chandra observations around the Galactic Centre. The nature of these sources is still unknown.

scholarly journals Statistical analysis of Galactic globular cluster type properties

2020 ◽  
Vol 495 (4) ◽  
pp. 3981-3989
Author(s):  
M Simioni ◽  
A Aparicio ◽  
G Piotto
Keyword(s):  
Globular Clusters ◽  
Principal Component ◽  
Slow Neutron ◽  
Galactic Centre ◽  
Type I ◽  
Type Ii ◽  
Relative Age ◽  
Average Complexity ◽  
Chromosome Maps ◽  
Cluster Type

ABSTRACT The analysis of pseudo-colour diagrams, the so-called chromosome maps, of Galactic globular clusters (GCs) permits to classify them into type I and type II clusters. Type II GCs are characterized by an above-the-average complexity of their chromosome maps and some of them are known to display star-to-star variations of slow neutron-capture reaction elements including iron. This is at the basis of the hypothesis that type II GCs may have an extragalactic origin and were subsequently accreted by the Milky Way. We performed a principal component analysis to explore possible correlations among various GCs parameters in the light of this new classification. The analysis revealed that cluster type correlates mainly with relative age. The cause of this relation was further investigated finding that more metal-rich type II clusters, also appear to be younger and more distant from the Galactic centre. A depletion of type II clusters for positive values of Galactic coordinate Z was also observed, with no type II clusters detected above Z ∼ 2 kpc. Type II cluster orbits also have larger eccentricities than type I ones.

Compare the Petrophysics of Formation Type I and II by Mercury Injection Curve Normalization

2014 ◽  
Vol 960-961 ◽  
pp. 258-261
Author(s):  
Ling Yun Chen ◽  
Yi Kun Liu ◽  
Li Hua Xia ◽  
Qian Liu
Keyword(s):  
Capillary Pressure ◽  
Thin Layers ◽  
Type I ◽  
Type Ii ◽  
Visual Identification ◽  
Mercury Injection ◽  
Order Of Magnitude ◽  
Formation Type ◽  
Capillary Pressure Curves ◽  
Developing Method

Study on Formation Type II is so few that affect on tapping the potential [2]. Analyzing petrophysics of Formation Type I and II by mercury injection curve normalization, it’s vital to developing method choice on tapping the potential of Formation Type II. Capillary pressure curves (Pc-curves) from conventional Mercury Injection are hard to analyze and compare because of various shapes. To get typical capillary pressure curves for Formation Type I and II, the curves from Mercury Injection is processed by Function J, and the J function curves and normalized Pc-curves for tabulated thin layers, tabulated thick layers and un-tabulated layers in Formation Type I and II, compare and analyze the influence of permeability on the shape of J function curves and normalized Pc-curves; compare the influence of different kinds of layers with the same permeability order of magnitude on the shape of J function curves and normalized Pc-curves, i.e. the influence of other factors except permeability, to get some visual identification methods and analyze the petrophysics difference between Formation Type I and II which is shown on Pc-curves.

scholarly journals A 1667 MHz OH Absorption Survey of the Southern Milky Way

1974 ◽  
Vol 27 (4) ◽  
pp. 597 ◽  
Author(s):  
JL Caswell ◽  
BJ Robinson
Keyword(s):  
Milky Way ◽  
Line Emission ◽  
The Other ◽  
Emission Sources ◽  
Satellite Line ◽  
Galactic Longitude

A search has been made at 1667 MHz for OH absorption against 105 strong continuum sources in the region 2650 < I < 352�, and data are presented for 33 sources showing absorption. The overall distribution of OH absorption in this galactic longitude range has been investigated by combining these results with measurements on 11 additional sources studied in earlier searches. Many of the sources showing 1667 MHz absorption have been observed at the other three 18 cm OH transitions and as a result 14 new satellite-line emission sources have been found.

scholarly journals A Southern Survey of OH Masers at 1612 MHz

1981 ◽  
Vol 34 (3) ◽  
pp. 333 ◽  
Author(s):  
JL Caswell ◽  
RF Haynes ◽  
WM Goss ◽  
U Mebold
Keyword(s):  
Galactic Plane ◽  
Galactic Centre ◽  
Emission Sources ◽  
Classification Schemes ◽  
Mira Variables ◽  
Population Type ◽  
Ir Stars ◽  
Kinematic Properties ◽  
Line Type

A search for OH at 1612 MHz has been made along the galactic plane from longitude 3400 to the galactic centre, yielding 78 emission sources (mostly new discoveries); a further 5 sources have been found in a less sensitive survey between longitudes 2700 and 3260 Of these 83 sources 55 are masers of the variety showing two intensity peaks spaced in velocity-a characteristic of OH/IR stars. The velocity and spatial distributions of these new OHjIR stars (which are not as yet identified in the optical or infrared) are discussed, with special reference to their kinematic properties and population type; it is still not clear whether they are predominantly late-type giants (Mira variables) or supergiants. The other 28 OH sources detected include 11 of the type lIe variety (extended OH clouds exhibiting 1612 MHz emission with accompanying 1720 MHz absorption) and 4 with accompanying main-line (type 1)OH masers; the remaining 13 sources do not readily fit within existing classification schemes and are discussed individually

scholarly journals Survey of OH Masers at 1665 and 1667 MHz. I. Galactic Longitudes 326° to 40°

1980 ◽  
Vol 33 (3) ◽  
pp. 639 ◽  
Author(s):  
JL Caswell ◽  
RF Haynes ◽  
WM Goss
Keyword(s):  
Supernova Remnants ◽  
Luminosity Function ◽  
Galactic Plane ◽  
Line Emission ◽  
Zeeman Splitting ◽  
State Transitions ◽  
Line Profiles ◽  
Polarization Data ◽  
Hii Region ◽  
Nonthermal Radio

The galactic plane between longitudes 3260 and 3400 has been searched for OH emiSSIOn and bsorption on the 1665 and 1667 MHz transitions. Forty main-line emission sources were detected (27 new ones, 13 previously known), and these constitute a sample complete to a weIl-defined lower intensity limit in this region of sky. Line profiles of all sources are shown and the statistics on variability and on the intensity ratios of the ground state transitions are summarized. The completeness of the sample encouraged us to make a first attempt to construct a luminosity function and to estimate the total number of such masers in our Galaxy. A study of the velocity structures showed these to be extremely varied, but none exceed a total range of 25 km s -1; combined velocity and polarization data are compatible with a Zeeman splitting origin for the circular polarization, and with this interpretation several sources yield an estimate for the line-of-sight magnetic field strength of a few mG. Preliminary investigations of the associations with other celestial objects indicate that many of the masers are loosely associated with HII region complexes, but in at least eight instances no HII regions have yet been detected; of these eight masers, two may be associated with supernova remnants and one with an unidentified nonthermal radio source.

scholarly journals Spatial Distribution of Pulsars and Supernova Remnants

1987 ◽  
Vol 40 (6) ◽  
pp. 837 ◽  
Author(s):  
AO Allakhverdiyev ◽  
OH Guseinov ◽  
IM Yusifov
Keyword(s):  
Spatial Distribution ◽  
Supernova Remnants ◽  
Galactic Plane ◽  
Close Binary System ◽  
Close Binary ◽  
Type I ◽  
Type Ii ◽  
Solar Mass ◽  
The Galaxy ◽  
Main Component

We show that the burst of Type I supernovas occurs about 108 years after the birth of the progenitor. This duration results in the main by the delay of the burst after the formation of a white dwarf of about one solar mass in a close binary system. The mass of the main component of this system is about 8M0 , and the mass of the secondary about 3M0 . These stars complete their evolution as Type I supernovas and are distributed along the galactic plane. Pulsars are formed about 107 years after the birth of their progenitors, and are accompanied by a Type II supernova. Pulsars therefore have an annular distribution in the Galaxy.

Inhibition of the CNA trigger process for arousal from hibernation

1976 ◽  
Vol 230 (4) ◽  
pp. 1018-1025 ◽  
Author(s):  
AL Beckman ◽  
TL Stanton ◽  
E Satinoff
Keyword(s):  
Mean Value ◽  
Ground Squirrels ◽  
Type I ◽  
Type Ii ◽  
Small Magnitude ◽  
Citellus Lateralis ◽  
Ceiling Temperature ◽  
Rate Of Increase ◽  
Formation Type ◽  
Duplicate Portion

Ground squirrels (Citellus lateralis) produced three distinct types of thermogenic response during hibernation. These responses were evoked spontaneously as well as after stimulation produced by brief handling, or after microinjection of acetylcholine into the midbrain reticular formation. Type I responses were characterized by small magnitude and a slow (mean rate, 0.03 degrees C/min), variable rising phase. Type II responses were characterized by a smooth, rapid rising phase with a mean rate of increase of 0.11 degrees C/min and by an abrupt reversal of the rising phase within a restricted ceiling temperature band with a mean value of 9.4 degrees C. The third type of response, full arousal, was characterized by a return of body temperature to euthermic (nonhibernating) levels and by an early rising phase that was indistinguishable from the rising phase of type II responses. This indicates that the rising phase of type II responses and the duplicate portion of full arousals are produced by a common neuronal mechanism that functions as the trigger for arousal from hibernation, and that this mechanism can be spontaneously inhibited when increasing internal temperature reaches a hibernation ceiling level.

scholarly journals GaLactic and Extragalactic All-sky Murchison Widefield Array (GLEAM) survey II: Galactic plane 345° < l < 67°, 180° < l < 240°

2019 ◽  
Vol 36 ◽  
Author(s):  
N. Hurley-Walker ◽  
P. J. Hancock ◽  
T. M. O. Franzen ◽  
J. R. Callingham ◽  
A. R. Offringa ◽  
...  
Keyword(s):  
Large Scale ◽  
Galactic Plane ◽  
Galactic Centre ◽  
Virtual Observatory ◽  
Compact Source ◽  
Multi Scale ◽  
Position Accuracy ◽  
Murchison Widefield Array ◽  
Galactic Longitude ◽  
Better Than

Abstract This work makes available a further $2\,860~\text{deg}^2$ of the GaLactic and Extragalactic All-sky Murchison Widefield Array (GLEAM) survey, covering half of the accessible galactic plane, across 20 frequency bands sampling 72–231 MHz, with resolution $4\,\text{arcmin}-2\,\text{arcmin}$ . Unlike previous GLEAM data releases, we used multi-scale CLEAN to better deconvolve large-scale galactic structure. For the galactic longitude ranges $345^\circ < l < 67^\circ$ , $180^\circ < l < 240^\circ$ , we provide a compact source catalogue of 22 037 components selected from a 60-MHz bandwidth image centred at 200 MHz, with RMS noise $\approx10-20\,\text{mJy}\,\text{beam}^{-1}$ and position accuracy better than 2 arcsec. The catalogue has a completeness of 50% at ${\approx}120\,\text{mJy}$ , and a reliability of 99.86%. It covers galactic latitudes $1^\circ\leq|b|\leq10^\circ$ towards the galactic centre and $|b|\leq10^\circ$ for other regions, and is available from Vizier; images covering $|b|\leq10^\circ$ for all longitudes are made available on the GLEAM Virtual Observatory (VO).server and SkyView.

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