scholarly journals Pulsar Searches at Effelsberg — Past, Present & Future

2000 ◽  
Vol 177 ◽  
pp. 11-16
Author(s):  
D.R. Lorimer ◽  
M. Kramer
Keyword(s):  
Radio Telescope ◽  
Galactic Plane ◽  
Progress Report ◽  
Galactic Centre ◽  
Bright Future ◽  
The World ◽  
Highly Dispersed ◽  
Pulsar Searches

AbstractIt is fair to say that pulsar searches with the 100-m Effelsberg telescope have had something of a checkered history — after all, for many years, this was the largest radio telescope in the world never to have found a pulsar! This situation has, happily, changed. In this review we summarize recent discoveries of weak pulsars along the Galactic plane, give a progress report on a survey for highly dispersed pulsars in the Galactic centre and, in the spirit of this meeting, speculate on what should be a bright future for pulsar searches with this instrument.

scholarly journals Pulsar Searches at Effelsberg

2004 ◽  
Vol 218 ◽  
pp. 133-134 ◽  
Author(s):  
B. Klein ◽  
M. Kramer ◽  
P. Müller ◽  
R. Wielebinski
Keyword(s):  
Radio Telescope ◽  
Galactic Center ◽  
Millisecond Pulsars ◽  
Highly Dispersed ◽  
L Band ◽  
Under Construction ◽  
5 Ghz ◽  
Key Aspects ◽  
Pulsar Searches

We report on the progress of our search for highly dispersed pulsars near the Galactic Center at 5 GHz using the 100-m radio telescope in Effelsberg. We also present key aspects of our new survey for millisecond pulsars at 21 cm in parts of the northern sky. This survey will greatly benefit from the L-band multibeam receiver and a new FFT-based backend which are currently under construction at the MPIfR.

scholarly journals Classical Cepheids and Galactic Structure

1995 ◽  
Vol 155 ◽  
pp. 155-164
Author(s):  
J.D. Fernie
Keyword(s):  
World Wide Web ◽  
Recent Work ◽  
World Wide ◽  
Galactic Plane ◽  
Galactic Structure ◽  
Space Distribution ◽  
Galactic Centre ◽  
Classical Cepheids ◽  
The World

AbstractIn this review I consider recent results on the space distribution of classical Cepheids, first dealing with their Z-distribution normal to the galactic plane, and second considering their X,Y components in the plane. In doing so, use is made of a new database of 505 stars known to be or likely to be classical Cepheids which has recently been compiled by Fernie et al. (1995) and which is available electronically on the World Wide Web at the URL http://ddo.astro.utoronto.ca/cepheids.html, and by anonymous ftp at perseus.astro.utoronto.ca (128.100.77.18) in the directory pub/cepheids.Following the discussion of space distribution, a review of recent work on Cepheid kinematics and the resulting determination of the distance to the galactic centre will be given.

scholarly journals Finding Pulsars at Parkes

2001 ◽  
Vol 18 (1) ◽  
pp. 1-11 ◽  
Author(s):  
R. N. Manchester
Keyword(s):  
Radio Telescope ◽  
Globular Clusters ◽  
Millisecond Pulsars ◽  
Statistical Estimates ◽  
Detection Algorithms ◽  
The World ◽  
Detection Instrument ◽  
Pulsar Searches ◽  
Galactic Distribution ◽  
Unique Individual

AbstractThere are many reasons why it is important to increase the number of known pulsars. Not only do pulsar searches continue to improve statistical estimates of, for example, pulsar birthrates, lifetimes and the Galactic distribution, but they continue to turn up interesting and, in some cases, unique individual pulsars. In the early days of pulsar astronomy, the Molonglo radio telescope led the world as a pulsar detection instrument. However, the Parkes radio telescope, with its frequency versatility and greater tracking ablility, combined with sensitive receivers and powerful computer detection algorithms, is now the world’s most successful telescope at finding pulsars. The Parkes multibeam survey, begun in 1997, by itself will come close to doubling the number of known pulsars. Parkes has also been very successful at finding millisecond pulsars (MSPs), especially in globular clusters. One third of the known MSPs have been found in just one cluster, 47 Tucanae.

scholarly journals Hydrogen motions in the central region of the Galaxy

1964 ◽  
Vol 20 ◽  
pp. 183-186 ◽  
Author(s):  
B. F. Burke ◽  
M. A. Tuve
Keyword(s):  
Radio Telescope ◽  
Cross Sections ◽  
Central Region ◽  
Galactic Plane ◽  
Circular Motion ◽  
Galactic Centre ◽  
Strong Deviation ◽  
The Galaxy

The 21-cm hydrogen radiation near the galactic plane exhibits strong deviation from circular motion over longitudes within 30° or so of the galactic centre. In order to extend the observations first made by Rougoor and Oort,* the Carnegie multichannel H-line spectrograph was used with our 60-foot radio telescope at Derwood, Maryland, in order to confirm the Leiden work and extend observations to more southern longitudes. Cross-sections extending ±2° in latitude were taken every 2° in longitude from lII=−26°8 to lII=+2°2 and a series of points along the galactic equator were taken every 1° over the same range. Effort has been concentrated on the southern extension of the observations, which agree well with the Leiden observations over the section in common, but which carry the observations nearly 20° farther south in longitude.

Interstellar gas in the central region of the Galaxy

1967 ◽  
Vol 31 ◽  
pp. 239-251 ◽  
Author(s):  
F. J. Kerr
Keyword(s):  
Central Region ◽  
Galactic Plane ◽  
Neutral Hydrogen ◽  
Continuum Emission ◽  
Galactic Centre ◽  
Interstellar Gas ◽  
Hydrogen Recombination ◽  
The Galaxy ◽  
Centre Region ◽  
The Relationship

A review is given of information on the galactic-centre region obtained from recent observations of the 21-cm line from neutral hydrogen, the 18-cm group of OH lines, a hydrogen recombination line at 6 cm wavelength, and the continuum emission from ionized hydrogen.Both inward and outward motions are important in this region, in addition to rotation. Several types of observation indicate the presence of material in features inclined to the galactic plane. The relationship between the H and OH concentrations is not yet clear, but a rough picture of the central region can be proposed.

Progress report on 21-cm observations at low latitude between longitudes (l 11) 0° and 66°

1967 ◽  
Vol 31 ◽  
pp. 177-179
Author(s):  
W. W. Shane
Keyword(s):  
Preliminary Report ◽  
Progress Report ◽  
Galactic Centre ◽  
Low Latitude ◽  
The Third ◽  
Introductory Lecture ◽  
Centre Region

In the course of several 21-cm observing programmes being carried out by the Leiden Observatory with the 25-meter telescope at Dwingeloo, a fairly complete, though inhomogeneous, survey of the regionl11= 0° to 66° at low galactic latitudes is becoming available. The essential data on this survey are presented in Table 1. Oort (1967) has given a preliminary report on the first and third investigations. The third is discussed briefly by Kerr in his introductory lecture on the galactic centre region (Paper 42). Burton (1966) has published provisional results of the fifth investigation, and I have discussed the sixth in Paper 19. All of the observations listed in the table have been completed, but we plan to extend investigation 3 to a much finer grid of positions.

scholarly journals Carbon Dots for Cancer Nanomedicine: A Bright Future

2021 ◽  
Author(s):  
Samer Bayda ◽  
Emanuele Amadio ◽  
Simone Cailotto ◽  
Yahima Frión-Herrera ◽  
Alvise Perosa ◽  
...  
Keyword(s):  
Early Diagnosis ◽  
Carbon Dots ◽  
Causes Of Death ◽  
Cancer Therapies ◽  
Therapeutic Approaches ◽  
Bright Future ◽  
Cancer Nanomedicine ◽  
The World

Cancer remains one of the main causes of death in the world. Early diagnosis and effective cancer therapies are required to treat this pathology. Traditional therapeutic approaches are limited by...

scholarly journals A 610-MHz Galactic Plane Pulsar Search with the Giant Meterwave Radio Telescope

2008 ◽  
Author(s):  
B. C. Joshi ◽  
M. A. McLaughlin ◽  
M. Kramer ◽  
A. G. Lyne ◽  
D. R. Lorimer ◽  
...  
Keyword(s):  
Radio Telescope ◽  
Galactic Plane

scholarly journals The evolutionary status of protostellar clumps hosting class II methanol masers

2020 ◽  
Vol 493 (2) ◽  
pp. 2015-2041 ◽  
Author(s):  
B M Jones ◽  
G A Fuller ◽  
S L Breen ◽  
A Avison ◽  
J A Green ◽  
...  
Keyword(s):  
Galactic Plane ◽  
Dust Emission ◽  
Principal Component ◽  
Far Infrared ◽  
Class Ii ◽  
Young Stellar Objects ◽  
Galactic Centre ◽  
Evolutionary Status ◽  
Methanol Maser ◽  
Methanol Masers

ABSTRACT The Methanol MultiBeam survey (MMB) provides the most complete sample of Galactic massive young stellar objects (MYSOs) hosting 6.7 GHz class II methanol masers. We characterize the properties of these maser sources using dust emission detected by the Herschel Infrared Galactic Plane Survey (Hi-GAL) to assess their evolutionary state. Associating 731 (73 per cent) of MMB sources with compact emission at four Hi-GAL wavelengths, we derive clump properties and define the requirements of an MYSO to host a 6.7 GHz maser. The median far-infrared (FIR) mass and luminosity are 630 M⊙ and 2500 L⊙ for sources on the near side of Galactic centre and 3200 M⊙ and 10000 L⊙ for more distant sources. The median luminosity-to-mass ratio is similar for both at ∼4.2 L⊙  M⊙−1. We identify an apparent minimum 70 μm luminosity required to sustain a methanol maser of a given luminosity (with $L_{70} \propto L_{6.7}\, ^{0.6}$). The maser host clumps have higher mass and higher FIR luminosities than the general Galactic population of protostellar MYSOs. Using principal component analysis, we find 896 protostellar clumps satisfy the requirements to host a methanol maser but lack a detection in the MMB. Finding a 70 μm flux density deficiency in these objects, we favour the scenario in which these objects are evolved beyond the age where a luminous 6.7 GHz maser can be sustained. Finally, segregation by association with secondary maser species identifies evolutionary differences within the population of 6.7GHz sources.

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.

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