Discovery prospects with the Dark-photons & Axion-Like particles Interferometer

We discuss the discovery potential of the Dark-photons & Axion-Like particles Interferometer (DALI) in this letter. The apparatus, currently in a design and prototyping phase, will probe axion dark matter from the Teide Observatory, an environment protected from terrestrial microwave sources, reaching Dine--Fischler--Srednicki--Zhitnitsky-like axion sensitivity in the range 25--250 $\mu$eV of mass. The experimental approach shows a potential to probe dark sector photons of kinetic mixing strength in excess of several $10^{-16}$, and to establish new constraints to a stochastic gravitational wave background in its band. We identify different branches, including cosmology, stellar, and particle physics, where this next-generation halo-telescope may play a role in coming years.Comment: As accepted by PRD [8 pages, 5 figures + Supplemental Material 4 pages, 3 figures]. https://journals.aps.org/prd/accepted/1f074Q62Pa91023535875f66ca556bf86dda6f46

A prescription for the conditional mass function of dark matter haloes

[ABRIDGED] The unconditional mass function (UMF) of dark matter haloes has been determined accurately in the literature, showing excellent agreement with high resolution numerical simulations. However, this is not the case for the conditional mass function (CMF). We propose a simple analytical procedure to derive the CMF by rescaling the UMF to the constrained environment using the appropriate mean and variance of the density field at the constrained point. This method introduces two major modifications with respect to the standard re-scaling procedure. First of all, rather than using in the scaling procedure the properties of the environment averaged over all the conditioning region, we implement the re-scaling locally. We show that for high masses this modification may lead to substantially different results. Secondly, we modify the (local) standard re-scaling procedure in such a manner as to force normalisation, in the sense that when one integrates the CMF over all possible values of the constraint multiplied by their corresponding probability distribution, the UMF is recovered. In practise, we do this by replacing in the standard procedure the value delta_c (the linear density contrast for collapse) by certain adjustable effective parameter delta_eff. In order to test the method, we compare our prescription with the results obtained from numerical simulations in voids (Gottlober et al. 2003), finding a very good agreement. Based on these results, we finally present a very accurate analytical fit to the (accumulated) conditional mass function obtained with our procedure, which may be useful for any theoretical treatment of the large scale structure.Comment: 14 pages, 10 figures. Accepted for publication in MNRA

Experimental measurement of the quality factor of a Fabry-P\'erot open-cavity axion haloscope

The axion is a hypothetical boson arising from the most natural solution to the problem of charge and parity symmetry in the strong nuclear force. Moreover, this pseudoscalar emerges as a dark matter candidate in a parameter space extending several decades in mass. The Dark-photons \& Axion-Like particles Interferometer (DALI) is a proposal to search for axion dark matter in a range that remains under-examined. Currently in a design and prototyping phase, this haloscope is a multilayer Fabry-P\'erot interferometer. A proof-of-principle experiment is performed to observe the resonance in a prototype. The test unveils a quality factor per open cavity of a few hundred over a bandwidth of the order of dozens of megahertz. The result elucidates a physics potential to find the, so far elusive, axion, in a sector which can simultaneously solve the symmetry problem in the strong interaction and the enigma of dark matter.Comment: 5 pages, 6 figure

Cosmic microwave background polarization receivers: QUIJOTE experiment

The QUIJOTE (Q U I JOint TEnerife) Experiment will characterize the polarization of Cosmic Microwave Background radiation and other galactic and extragalactic emissions in the frequency range from 10 to 30 GHz, and at large angular scales. The polarimeter receivers at 11, 13, 17, 19 and 30 GHz are radiometers based on broadband waveguide rotating polar modulators and broadband orthomode transducers. High sensitivity of polarimeters is achieved with very low noise cryogenic amplifiers (Noise temperature < 15 K in 11-19 GHz channels and < 20 K in 30 GHz channel). Subsystems test results and integration measurements of front-end and back-end units show wideband operation in all channels.This work has been funded by the Ministerio de Educación y Ciencia (Spain) under Astronomy and Astrophysics program, reference AYA2007-68058-C03

QUIJOTE scientific results - IX. Radio sources in the QUIJOTE-MFI wide survey maps

We present the catalogue of Q-U-I JOint TEnerife (QUIJOTE) Wide Survey radio sources extracted from the maps of the Multi-Frequency Instrument compiled between 2012 and 2018. The catalogue contains 786 sources observed in intensity and polarization, and is divided into two separate sub-catalogues: one containing 47 bright sources previously studied by the Planck collaboration and an extended catalogue of 739 sources either selected from the Planck Second Catalogue of Compact Sources or found through a blind search carried out with a Mexican Hat 2 wavelet. A significant fraction of the sources in our catalogue (38.7 per cent) are within the |b| ≤ 20◦ region of the Galactic plane. We determine statistical properties for those sources that are likely to be extragalactic. We find that these statistical properties are compatible with currently available models, with a ∼1.8 Jy completeness limit at 11 GHz. We provide the polarimetric properties of (38, 33, 31, 23) sources with P detected above the 99.99 per cent significance level at (11, 13, 17, 19) GHz respectively. Median polarization fractions are in the 2.8–4.7 per cent range in the 11–19 GHz frequency interval. We do not distinguish between Galactic and extragalactic sources here. The results presented here are consistent with those reported in the literature for flat- and steep-spectrum radio sources.We thank the staff of the Teide Observatory for invaluable assistance in the commissioning and operation of QUIJOTE. The QUIJOTE experiment is being developed by the Instituto de Astrofísica de Canarias (IAC), the Instituto de Física de Cantabria (IFCA), and the Universities of Cantabria, Manchester and Cambridge. Partial financial support was provided by the Spanish Ministry of Science and Innovation under the projects AYA2007-68058-C03-01, AYA2007- 68058-C03-02, AYA2010-21766-C03-01, AYA2010-21766-C03-02, AYA2014-60438-P, ESP2015-70646-C2-1-R, AYA2017-84185-P, ESP2017-83921-C2-1-R, AYA2017-90675-REDC (co-funded with EU FEDER funds), PGC2018-101814-B-I00, PID2019-110610RBC21, PID2020-120514GB-I00, IACA13-3E-2336, IACA15-BE3707, EQC2018-004918-P, the Severo Ochoa Programs SEV-2015- 0548 and CEX2019-000920-S, the María de Maeztu Program MDM-2017-0765, and by the Consolider-Ingenio project CSD2010- 00064 (EPI: Exploring the Physics of Inflation). DT acknowledges the support from the Chinese Academy of Sciences (CAS) President’s International Fellowship Initiative (PIFI) with Grant N. 2020PM0042. FP acknowledges support from the Spanish State Research Agency (AEI) under grant number PID2019-105552RBC43. We acknowledge support from the ACIISI, Consejería de Economía, Conocimiento y Empleo del Gobierno de Canarias, and the European Regional Development Fund (ERDF) under grant with reference ProID2020010108. This project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement number 687312 (RADIOFOREGROUNDS). This research has made use of data from the OVRO 40-m monitoring program (Richards et al. 2011), supported by private funding from the California Insitute of Technology and the Max Planck Institute forRadio Astronomy, and by NASA grants NNX08AW31G, NNX11A043G, and NNX14AQ89G and NSF grants AST-0808050 and AST-1109911. Some of the results in this paper have been derived using the HEALPY and HEALPIX packages (Gorski et al. 2005; Zonca et al. 2019). The packages ASTROPY (Astropy Collaboration 2013, 2018), SCIPY (Virtanen et al. 2020), MATPLOTLIB (Hunter 2007), NUMPY (Harris et al. 2020), and EMCEE (Foreman-Mackey et al. 2013) have been extensively used for data analysis and plotting

A Very Small Array search for the extended Sunyaev-Zel'dovich effect in the Corona Borealis supercluster

We present interferometric imaging at 33 GHz of the Corona Borealis supercluster, using the extended configuration of the Very Small Array. A total area of 24 deg² has been imaged, with an angular resolution of 11 arcmin and a sensitivity of 12 mJy beam⁻¹. The aim of these observations is to search for Sunyaev-Zel'dovich (SZ) detections from known clusters of galaxies in this supercluster and for a possible extended SZ decrement due to diffuse warm/hot gas in the intercluster medium. Hydrodynamical simulations suggest that a significant part of the missing baryons in the Local Universe may be located in superclusters. The maps constructed from these observations have a significant contribution from primordial fluctuations. We measure negative flux values in the positions of the 10 richest clusters in the region. Collectively, this implies a 3.0σ detection of the SZ effect. For two of these clusters, A2061 and A2065, we find decrements of approximately 2σ each. Our main result is the detection of two strong and resolved negative features at −70 ± 12 mJy beam⁻¹ (−157 ± 27 μK) and −103 ± 10 mJy beam⁻¹ (−230 ± 23 μK), respectively, located in a region with no known clusters, near the centre of the supercluster. We discuss their possible origins in terms of primordial cosmic microwave background (CMB) anisotropies and/or SZ signals related either to unknown clusters or to a diffuse extended warm/hot gas distribution. Our analyses have revealed that a primordial CMB fluctuation is a plausible explanation for the weaker feature (probability of 37.82 per cent). For the stronger one, neither primordial CMB (probability of 0.38 per cent) nor SZ can account alone for its size and total intensity. The most reasonable explanation, then, is a combination of both primordial CMB and SZ signal. Finally, we explore what characteristics would be required for a filamentary structure consisting of warm/hot diffuse gas in order to produce a significant contribution to such a spot taking into account the constraints set by X-ray data

A Very Small Array search for the extended Sunyaev-Zel'dovich effect in the Corona Borealis supercluster

We present interferometric imaging at 33 GHz of the Corona Borealis supercluster, using the extended configuration of the Very Small Array. A total area of 24 deg² has been imaged, with an angular resolution of 11 arcmin and a sensitivity of 12 mJy beam⁻¹. The aim of these observations is to search for Sunyaev-Zel'dovich (SZ) detections from known clusters of galaxies in this supercluster and for a possible extended SZ decrement due to diffuse warm/hot gas in the intercluster medium. Hydrodynamical simulations suggest that a significant part of the missing baryons in the Local Universe may be located in superclusters. The maps constructed from these observations have a significant contribution from primordial fluctuations. We measure negative flux values in the positions of the 10 richest clusters in the region. Collectively, this implies a 3.0σ detection of the SZ effect. For two of these clusters, A2061 and A2065, we find decrements of approximately 2σ each. Our main result is the detection of two strong and resolved negative features at −70 ± 12 mJy beam⁻¹ (−157 ± 27 μK) and −103 ± 10 mJy beam⁻¹ (−230 ± 23 μK), respectively, located in a region with no known clusters, near the centre of the supercluster. We discuss their possible origins in terms of primordial cosmic microwave background (CMB) anisotropies and/or SZ signals related either to unknown clusters or to a diffuse extended warm/hot gas distribution. Our analyses have revealed that a primordial CMB fluctuation is a plausible explanation for the weaker feature (probability of 37.82 per cent). For the stronger one, neither primordial CMB (probability of 0.38 per cent) nor SZ can account alone for its size and total intensity. The most reasonable explanation, then, is a combination of both primordial CMB and SZ signal. Finally, we explore what characteristics would be required for a filamentary structure consisting of warm/hot diffuse gas in order to produce a significant contribution to such a spot taking into account the constraints set by X-ray data

The new multi-frequency instrument (MFI2) for the QUIJOTE facility in Tenerife

The QUIJOTE (Q-U-I joint Tenerife) experiment combines the operation of two radio-telescopes and three instruments working in the microwave bands 10?20 GHz, 26-36 GHz and 35-47 GHz at the Teide Observatory, Tenerife, and has already been presented in previous SPIE meetings (Hoyland, R. J. et al, 2012; Rubiño-Martín et al., 2012). The Cosmology group at the IAC have designed a new upgrade to the MFI instrument in the band 10-20 GHz. The aim of the QUIJOTE telescopes is to characterise the polarised emission of the cosmic microwave background (CMB), as well as galactic and extra-galactic sources, at medium and large angular scales. This MFI2 will continue the survey at even higher sensitivity levels. The MFI2 project led by the Instituto de Astrofísica de Canarias (IAC) consists of five polarimeters, three of them operating in the sub-band 10?15 GHz, and two in the sub-band 15-20 GHz. The MFI2 instrument is expected to be a full two-three times more sensitive than the former MFI. The microwave complex correlator design has been replaced by a simple correlator design with a digital back-end based on the latest Xilinx FPGAs (ZCU111). During the first half of 2019 the manufacture of the new cryostat was completed and since then the opto-mechanical components have been designed and manufactured. It is expected that the cryogenic front-end will be completed by the end of 2022 along with the FPGA acquisition and observing system. This digital system has been employed to be more robust against stray ground-based and satellite interference, having a frequency resolution of 1 MHz.The MFI2 instrument is being developed by the Instituto de Astrofisica de Canarias (IAC), with an instrumental participation from the Universidad Politecnica de Cartagena (UPCT). Partial financial support is provided by the Spanish Ministry of Science and Innovation (MICINN), under the projects AYA2017-84185-P, IACA15-BE-3707, EQC2018-004918-P and the FEDER Agreement INSIDE-OOCC (ICTS-2019-03-IAC-12). We also acknowledge financial support of the Severo Ochoa Programs SEV-2015-0548 and CEX2019-000920-S