The brightness of the galactic radio loops at 1420 MHz: Some indications for the existence of Loops V and VI
Апстракт
In this article we use 1420 MHz data to demonstrate the likely reality of Galactic radio Loops V and VI. We further estimate distances and spectral indices for both these and the four main radio loops. In the cases of Loops I-IV, radio spectral indices are calculated from the mean brightnesses at 1420 and 820/404 MHz. The spectral indices of Loops V and VI are obtained from T-T plots between 1420 and 408 MHz. Using the supernova remnant (SNR) hypothesis for the origin of radio loops, distances are calculated from the surface brightnesses and the angular diameters at 1420 MHz. We also study how results for brightnesses and distances of radio loops agree with current theories of SNR evolution. For this purpose, the ambient density and initial explosion energy of the loops are discussed. We also discuss applications of different Q-D relations. The results obtained confirm a non-thermal origin and nearby locations for the Galactic radio loops. Therefore, we have indications that they are v...ery old SNRs that evolve in low ambient densities, with high initial explosion energies. (C) 2008 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim.
Кључне речи:
ISM : supernova remnants / radio continuum : general / radiation mechanisms : non-thermal / surveysИзвор:
Astronomische Nachrichten, 2008, 329, 4, 397-402
DOI: 10.1002/asna.200610927
ISSN: 0004-6337
WoS: 000256049000009
Scopus: 2-s2.0-55549102685
Колекције
Институција/група
VinčaTY - JOUR AU - Borka Jovanović, Vesna AU - Milogradov-Turin, J. AU - Urosevic, D. PY - 2008 UR - https://vinar.vin.bg.ac.rs/handle/123456789/3447 AB - In this article we use 1420 MHz data to demonstrate the likely reality of Galactic radio Loops V and VI. We further estimate distances and spectral indices for both these and the four main radio loops. In the cases of Loops I-IV, radio spectral indices are calculated from the mean brightnesses at 1420 and 820/404 MHz. The spectral indices of Loops V and VI are obtained from T-T plots between 1420 and 408 MHz. Using the supernova remnant (SNR) hypothesis for the origin of radio loops, distances are calculated from the surface brightnesses and the angular diameters at 1420 MHz. We also study how results for brightnesses and distances of radio loops agree with current theories of SNR evolution. For this purpose, the ambient density and initial explosion energy of the loops are discussed. We also discuss applications of different Q-D relations. The results obtained confirm a non-thermal origin and nearby locations for the Galactic radio loops. Therefore, we have indications that they are very old SNRs that evolve in low ambient densities, with high initial explosion energies. (C) 2008 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim. T2 - Astronomische Nachrichten T1 - The brightness of the galactic radio loops at 1420 MHz: Some indications for the existence of Loops V and VI VL - 329 IS - 4 SP - 397 EP - 402 DO - 10.1002/asna.200610927 ER -
@article{ author = "Borka Jovanović, Vesna and Milogradov-Turin, J. and Urosevic, D.", year = "2008", abstract = "In this article we use 1420 MHz data to demonstrate the likely reality of Galactic radio Loops V and VI. We further estimate distances and spectral indices for both these and the four main radio loops. In the cases of Loops I-IV, radio spectral indices are calculated from the mean brightnesses at 1420 and 820/404 MHz. The spectral indices of Loops V and VI are obtained from T-T plots between 1420 and 408 MHz. Using the supernova remnant (SNR) hypothesis for the origin of radio loops, distances are calculated from the surface brightnesses and the angular diameters at 1420 MHz. We also study how results for brightnesses and distances of radio loops agree with current theories of SNR evolution. For this purpose, the ambient density and initial explosion energy of the loops are discussed. We also discuss applications of different Q-D relations. The results obtained confirm a non-thermal origin and nearby locations for the Galactic radio loops. Therefore, we have indications that they are very old SNRs that evolve in low ambient densities, with high initial explosion energies. (C) 2008 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim.", journal = "Astronomische Nachrichten", title = "The brightness of the galactic radio loops at 1420 MHz: Some indications for the existence of Loops V and VI", volume = "329", number = "4", pages = "397-402", doi = "10.1002/asna.200610927" }
Borka Jovanović, V., Milogradov-Turin, J.,& Urosevic, D.. (2008). The brightness of the galactic radio loops at 1420 MHz: Some indications for the existence of Loops V and VI. in Astronomische Nachrichten, 329(4), 397-402. https://doi.org/10.1002/asna.200610927
Borka Jovanović V, Milogradov-Turin J, Urosevic D. The brightness of the galactic radio loops at 1420 MHz: Some indications for the existence of Loops V and VI. in Astronomische Nachrichten. 2008;329(4):397-402. doi:10.1002/asna.200610927 .
Borka Jovanović, Vesna, Milogradov-Turin, J., Urosevic, D., "The brightness of the galactic radio loops at 1420 MHz: Some indications for the existence of Loops V and VI" in Astronomische Nachrichten, 329, no. 4 (2008):397-402, https://doi.org/10.1002/asna.200610927 . .