A new spectrum analyzer for radio astronomical studies with the radio telescope RATAN-600

Логвиненко, С. В.; Venger, A. P.; Ильин, Г. Н.; Дубрович, В. К.; Morozov, A. S.

doi:10.1134/s1990341308020090

Cited by 5 publications

(1 citation statement)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…An uncooled HEMT transistor amplifier [8] was used at the input, and the noise temperature of the system was equal to 70-80 K. A 2048-channel Fourier analyzer with a channel bandwidth of 29.3 kHz was used to analyze the spectra [9]. The first observations did not make use of the full bandwidth (60 MHz) of the spectral analyzer due to the insufficient bandwidth of the receiver.…”

Section: Equipment and Techniquementioning

confidence: 99%

Spectral and spatial fluctuations of cosmic microwave background radiation. RATAN-600 radio telescope observations with a Fourier spectral analyzer

2012

Self Cite

View full text Add to dashboard Cite

The "circumpolar survey" technique allowed us to achieve a rather high antenna temperature sensitivity of 0.5 mK at 6 cm on a fixed antenna with a relatively narrow frequency resolution band (600 kHz) and an angular resolution of 45 × 7 . Starting from 2007 we use a Fourier spectral analyzer with a survey band 10 times broader than that of previous observations. This upgrade allowed us to rapidly perform repeated test observations, which confirmed the power-law nature and the frequency structure of spatial spectra in two strips in the vicinity of the celestial pole in the 4 -16 interval of angular periods. These observations also showed that the Galactic CH molecular line that was by chance captured in our survey strip (Λ-doubling of rotational transition) has nothing to do with the emission spectra we obtained. The angular pattern of emission in two main lines of Λ-doubling (4847.84 and 4870.12 MHz) is absolutely different, whereas there is practically no maser amplification in the CH line to explain this fact. Our observations also confirm the H 110 α line (4874.157 MHz), which forms in the tenuous ionized Galactic hydrogen at such relatively high latitudes. Other features of the spatial spectra also appear to be quite real, although their interpretation remains unclear and requires further studies.

show abstract

Section: Equipment and Techniquementioning

confidence: 99%

Spectral and spatial fluctuations of cosmic microwave background radiation. RATAN-600 radio telescope observations with a Fourier spectral analyzer

2012

Self Cite

View full text Add to dashboard Cite

show abstract

3D spectroscopy of merger Seyfert galaxy Mrk 334: nuclear starburst, superwind and the circumnuclear cavern

Smirnova¹,

Моисеев²

2010

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

We are presenting new results on kinematics and structure of the Mrk 334 Seyfert galaxy. Panoramic (3D) spectroscopy is performed at the 6-m telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences using the integral-field Multi-Pupil Fiber Spectrograph (MPFS) and scanning Fabry-Pérot interferometer. The deep images have revealed that Mrk 334 is observed during the final stage of its merging with a massive companion. A possible mass ratio ranges from 1/5 to 1/3. The merger has triggered mass redistribution in the disc resulting in an intensification of nuclear activity and in a burst of star formation in the inner region of the galaxy. The circumnuclear starburst is so intense that its contribution to the gas ionization exceeds that contribution of the active galactic nuclei (AGN). We interpret the nuclear gas outflow with velocities of ∼200 km s −1 as a galactic superwind that accompanies the violent star formation. This suggestion is consistent with the asymmetric X-ray brightness distribution in Mrk 334. The trajectory of the fragments of the disrupted satellite in the vicinity of the main galaxy nucleus can be traced. In the galaxy disc, a cavern is found that is filled with a low-density ionized gas. We consider this region to be the place where the remnants of the companion have recently penetrated through the gaseous disc of the main galaxy.

show abstract

On the nature of the apparent ring galaxy SDSS J075234.33+292049.8

Brosch

Kniazev

Моисеев

et al. 2010

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

We show that an object classified as a galaxy in on‐line data bases and revealed on sky survey images as a distant ring galaxy is a rare case of polar ring galaxy (PRG) where the ring is only slightly inclined to the equatorial plane of the central body (CB). Imaging information from the Sloan Digital Sky Survey (SDSS) indicates that the diameter of the ring is about 36 kpc. The SDSS data was combined with long‐slit spectroscopic observations and with Fabry–Pérot interferometer Hβ mapping obtained at the Russian Academy of Sciences 6‐m telescope. We derived the complex morphologies of this presumed ring galaxy from a combination of SDSS images and from the kinematical behaviour of the CB and of the ring, and determined the stellar population compositions of the two components from the SDSS colours, from the spectroscopy and from models of evolutionary stellar synthesis. The metallicity of the ring material is slightly underabundant. The total luminosity and the total mass of the system are not extreme, but the rather high M/L ≃ 20 indicates the presence of large amounts of dark matter. We propose two alternative explanations of the appearance of this object. One is a ring formed by two semicircular and tight spiral arms at the end of a central bar. The apparent inclination between the ring and the CB, and a strange kink at the north‐east end of the ring, could be the result of a warp or of precession of the ring material. The object could, therefore, be explained as an extreme SBa(R) galaxy. The other possibility is that we observe a PRG where the inner object is an S0 and the ring is significantly more luminous than the central object. The compound object would then be similar to the NGC 4650A galaxy, but then it would be a rare object, with a polar component only modestly inclined to the equatorial plane of the CB. Arguments for (and against) both explanations are given and discussed, with the second alternative being more acceptable.

show abstract

A new spectrum analyzer for radio astronomical studies with the radio telescope RATAN-600

Cited by 5 publications

References 0 publications

Spectral and spatial fluctuations of cosmic microwave background radiation. RATAN-600 radio telescope observations with a Fourier spectral analyzer

Spectral and spatial fluctuations of cosmic microwave background radiation. RATAN-600 radio telescope observations with a Fourier spectral analyzer

3D spectroscopy of merger Seyfert galaxy Mrk 334: nuclear starburst, superwind and the circumnuclear cavern

On the nature of the apparent ring galaxy SDSS J075234.33+292049.8

Contact Info

Product

Resources

About