Statistical techniques for future surveys: extracting primordial physics out of the large-scale structure

• Grant number: 18/10396-2
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: September 01, 2018
• End date: December 31, 2021
• Field of knowledge: Physical Sciences and Mathematics - Physics - Elementary Particle Physics and Fields
• Principal Investigator: Luis Raul Weber Abramo
• Grantee: Caroline Macedo Guandalin
• Host Institution: Instituto de Física (IF). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Inflation produces an approximately Gaussian spectrum of scale-independent density perturbations. Deviations from scale independence and from Gaussianity are key indicators of the physical processes behind inflation and can reveal to us the physical nature of the field(s) responsible for this phase of the Universe. Primordial non-Gaussianity (pNG) is manifested both in the cosmic microwave background and in the matter distribution in the Universe. As a result of new planned survey instruments, galaxy maps may be able to constrain f_NL (the main parameter that controls non-Gaussianity) better than the Planck satellite has been able to do. It may be possible even to measure parameters which control the "shape'' of the non-Gaussianities, such as g_NL. The main difficulties are, of course, the proper control of large-scale systematics, which mix up with the signal we are trying to measure. We have three main goals in this project: (1) apply the tools already implemented by the student during her M. Sc. work to real data in order to check their functionality and to constraint pNG parameters; (2) introduce pNG in the multi-tracer code she already worked with and determine the level and form of the expected systematics (photometric redshifts, scale-dependent bias, etc.) for some of the recent galaxy surveys (e.g. J-PAS and PFS) such that we are able to recover the signal in the presence of these systematics and (3) develop the multi-tracer technique for the bispectrum and test if this improves the constraints on pNG parameters.

Scientific publications

(4)

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

COATES, LOUIS; ADAMEK, JULIAN; BULL, PHILIP; GUANDALIN, CAROLINE; CLARKSON, CHRIS. bserving relativistic features in large-scale structure surveys - II. Doppler magnification in an ensemble of relativistic simulation. Monthly Notices of the Royal Astronomical Society, v. 504, n. 3, p. 3534-3543, JUL 2021. (18/10396-2)

GUANDALIN, CAROLINE; ADAMEK, JULIAN; BULL, PHILIP; CLARKSON, CHRIS; ABRAMO, L. RAUL; COATES, LOUIS. Observing relativistic features in large-scale structure surveys - I. Multipoles of the power spectrum. Monthly Notices of the Royal Astronomical Society, v. 501, n. 2, p. 2547-2561, FEB 2021. (18/10396-2, 18/04683-9)

COATES, LOUIS; ADAMEK, JULIAN; BULL, PHILIP; GUANDALIN, CAROLINE; CLARKSON, CHRIS. Observing relativistic features in large-scale structure surveys - II. Doppler magnification in an ensemble of relativistic simulations. Monthly Notices of the Royal Astronomical Society, v. 504, n. 3, p. 10-pg., 2021-05-07. (18/10396-2)

GUANDALIN, CAROLINE; CARUCCI, ISABELLA P.; ALONSO, DAVID; MOODLEY, KAVILAN. Clustering redshifts with the 21cm-galaxy cross-bispectrum. Monthly Notices of the Royal Astronomical Society, v. 516, n. 2, p. 20-pg., 2022-09-14. (18/10396-2)

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

GUANDALIN, Caroline Macedo. Statistical techniques for future surveys: extracting fundamental physics out of the large-scale structure. 2021. Doctoral Thesis - Universidade de São Paulo (USP). Instituto de Física (IF/SBI) São Paulo.