QUIJOTE scientific results - V. The microwave intensity and polarization spectra of the Galactic regions W49, W51 and IC443

Tramonte, D.; Génova-Santos, R. T.; Rubiño-Martín, J. A.; Vielva, P.; Poidevin, F.; López-Caraballo, C. H.; Peel, M. W.; Ashdown, M.; Artal, E.; Barreiro, R. B.; Casas, F. J.; de la Hoz, E.; Fernández-Torreiro, M.; Guidi, F.; Herranz, D.; Hoyland, R. J.; Lasenby, A. N.; Martinez-Gonzalez, E.; Piccirillo, L.; Rebolo, R.; Ruiz-Granados, B.; Vansyngel, F.; Watson, R. A.
Bibliographical reference

Monthly Notices of the Royal Astronomical Society

Advertised on:
3
2023
Number of authors
23
IAC number of authors
12
Citations
6
Refereed citations
5
Description
We present new intensity and polarization maps obtained with the QUIJOTE experiment towards the Galactic regions W49, W51 and IC443, covering the frequency range from 10 to 20 GHz at $\sim 1\, \text{deg}$ angular resolution, with a sensitivity in the range 35-79 $\mu \text{K}\, \text{beam}^{-1}$ for total intensity and 13-23 $\mu \text{K}\, \text{beam}^{-1}$ for polarization. For each region, we combine QUIJOTE maps with ancillary data at frequencies ranging from 0.4 to 3000 GHz, reconstruct the spectral energy distribution and model it with a combination of known foregrounds. We detect anomalous microwave emission (AME) in total intensity towards W49 at 4.7σ and W51 at 4.0σ with peak frequencies $\nu _{\rm AME}=(20.0\pm 1.4)\, \text{GHz}$ and $\nu _{\rm AME}=(17.7\pm 3.6)\, \text{GHz}$, respectively; this is the first detection of AME towards W51. The contamination from ultracompact H II regions to the residual AME flux density is estimated at 10 per cent in W49 and 5 per cent in W51, and does not rule out the AME detection. The polarized SEDs reveal a synchrotron contribution with spectral indices αs = -0.67 ± 0.10 in W49 and αs = -0.51 ± 0.07 in W51, ascribed to the diffuse Galactic emission and to the local supernova remnant, respectively. Towards IC443 in total intensity we measure a broken power-law synchrotron spectrum with cut-off frequency $\nu _{\rm 0,s}=(114\pm 73)\, \text{GHz}$, in agreement with previous studies; our analysis, however, rules out any AME contribution which had been previously claimed towards IC443. No evidence of polarized AME emission is detected in this study.
Related projects
The QUIJOTE experiment at the Teide Observatory
QUIJOTE CMB Experiment (Q-U-I JOint TEnerife CMB Experiment)
QUIJOTE es un programa de dos telescopios y su batería de instrumentos, instalados en el Observatorio del Teide, dedicados fundamentalmente a la caracterización de la polarización del Fondo Cósmico de Microondas, en el rango de frecuencias de 10-42 GHz.
José Alberto
Rubiño Martín
Full-sky map showing the spatial distribution of the primary anisotropies of the Cosmic Microwave Background (generated 380,000 years after the Big Bang) derived from observations of the Planck satellite
Anisotropy of the Cosmic Microwave Background
The general goal of this project is to determine and characterize the spatial and spectral variations in the temperature and polarisation of the Cosmic Microwave Background in angular scales from several arcminutes to several degrees. The primordial matter density fluctuations which originated the structure in the matter distribution of the present
Rafael
Rebolo López