arXiv subjects

Gianmarco Maggio

Publications and source records attributed to Gianmarco Maggio.

3 recordsLinked to original sources

arXiv2021

Revised planet brightness temperatures using the Planck/LFI 2018 data release

We present new estimates of the brightness temperatures of Jupiter, Saturn, Uranus, and Neptune based on the measurements carried in 2009--2013 by PLANCK/LFI at 30, 44, and 70 GHz and released to the public in 2018. This work extends the results presented in the 2013 and 2015 PLANCK/LFI Calibration Papers, based on the data acquired in 2009--2011. PLANCK observed each planet up to eight times during the nominal mission. We processed time-ordered data from the 22 LFI radiometers to derive planet antenna temperatures for each planet and transit. We accounted for the beam shape, radiometer bandpasses, and several systematic effects. We compared our results with the results from the ninth year of WMAP, PLANCK/HFI observations, and existing data and models for planetary microwave emissivity. For Jupiter, we obtain Tb = 144.9, 159.8, 170.5 K (+/- 0.2 K at 1 sigma, with temperatures expressed using the Rayleigh-Jeans scale) at 30, 44 and 70 GHz, respectively, or equivalently a band averaged Planck temperature TbBA=144.7$, 160.3, 171.2 K in good agreement with WMAP and existing models. A slight excess at 30 GHz with respect to models is interpreted as an effect of synchrotron emission. Our measures for Saturn agree with the results from WMAP for rings Tb = 9.2 +/- 1.4, 12.6 +/- 2.3, 16.2 +/- 0.8 K, while for the disc we obtain Tb = 140.0 +/- 1.4, 147.2 +/- 1.2, 150.2 +/- 0.4 K, or equivalently a TbBA=139.7, 147.8, 151.0 K. Our measures for Uranus (Tb = 152 +/- 6, 145 +/- 3, 132.0 +/- 2 K, or TbBA=152, 145, 133 K and Neptune Tb = 154 +/- 11, 148 +/- 9, 128 +/- 3 K, or TbBA=154 , 149, 128 K) agree closely with WMAP and previous data in literature.

astro-ph.EP↗

arXiv2020

CHIPP: INAF pilot project for HTC, HPC and HPDA

CHIPP (Computing HTC in INAF Pilot Project) is an Italian project funded by the Italian Institute for Astrophysics (INAF) and promoted by the ICT office of INAF. The main purpose of the CHIPP project is to coordinate the use of, and access to, already existing high throughput computing and high-performance computing and data processing resources (for small/medium size programs) for the INAF community. Today, Tier2/Tier3 systems (1,200 CPU/core) are provided at the INAF institutes at Trieste and Catania, but in the future, the project will evolve including also other computing infrastructures. During the last two years, more than 30 programs have been approved for a total request of 30 Million CPU-h. Most of the programs are HPC, data reduction and analysis, machine learning. In this paper, we describe in details the CHIPP infrastructures and the results of the first two years of activity.

astro-ph.IM↗

arXiv2016

A note on the birefringence angle estimation in CMB data analysis

Parity violating physics beyond the standard model of particle physics induces a rotation of the linear polarization of photons. This effect, also known as cosmological birefringence (CB), can be tested with the observations of the cosmic microwave background (CMB) anisotropies which are linearly polarized at the level of $5-10\%$. In particular CB produces non-null CMB cross correlations between temperature and B mode-polarization, and between E- and B-mode polarization. Here we study the properties of the so called D-estimators, often used to constrain such an effect. After deriving the framework of both frequentist and Bayesian analysis, we discuss the interplay between birefringence and weak-lensing, which, albeit parity conserving, modifies pre-existing TB and EB cross correlation.

astro-ph.CO↗