Skip to main content
Serena Giardiello

Dr Serena Giardiello

Research Associate

School of Physics and Astronomy

Queen's Buildings - North Building, Room N/3.20A, 5 The Parade, Newport Road, Cardiff, CF24 3AA


I work in Cosmology, studying in particular the Cosmic Microwave Background. I am a member of the LiteBIRD, Simons Observatory (SO) and Atacama Cosmology Telescope (ACT) collaborations.

I mainly study how systematic effects in CMB experiments propagate in the data analysis to the estimate of cosmological parameters. I am involved in the development of simulations and analysis pipelines for the collaborations I joined.

I joined Cardiff University in November 2022. Previously, I was a PhD candidate at Ferrara University in Italy.







My current research activity is mainly focused on the study of the propagation of systematic effects in experiments observing the Cosmic Microwave Background (CMB).

Half-Wave Plate systematics

For the upcoming LiteBIRD satellite, I have studied the half-wave plate (HWP) systematics and their effect on the constraints on the amplitude of primordial gravitational waves. The HWP is an optical element that will help achieving a higher sensitivity B-mode signal. The quest for primordial B-modes is one of the main goals of forthcoming CMB experiments: observing this signal will allow to constrain the amplitude of a (possible) primordial gravitational wave background, which would be the smoking-gun of inflationary mechanisms. Characterizing any possible systematic effects that contaminates the primordial signal is thus vital.

I am also studying the joint effect of HWP systematics and out-of-band contamination signal.

Study of systematic effects on small scales CMB power spectra 

For the ground-based Simons Observatory, I am studying the propagation of systematic effects related to bandpasses, calibration and polarization angle on the constraining power of the high-ell CMB data collected by the Large Aperture Telescope (LAT). The study of small scales CMB power spectra will allow to better constrain the radiation and particle content of the Universe, the weak gravitational lensing, the Sunyaev-Zeldovich effect (among many science cases). We study how these classes of systematics affect the estimate of both cosmological and foreground parameters. My activity includes the development of the LAT likelihood code (LAT_MFLike), which will be relevant also for the forthcoming ACT dr6 data analysis.

Probing Lorentz violation with CMB polarization

CMB polarization data can be used to constrain models of Lorentz-violating electrodynamics. We derived the modified propagation of CMB photons due to a non standard EM Lagrangian and computed from that the CMB power spectra affected by phenomenological Lorentz-violating parameters. The model taken into account generates both cosmic birefringence and circular polarization. We used the most recent CMB polarization data to set competitive constraints on these Lorentz-violating parameters.



  • 10/20 - 09/21: Assistant for the course of Statistics and models of experimental data, Master Degree in Mechanical Engineering, Università degli Studi di Ferrara, Italy
  • 01/20 - 05/20: Tutor of Physics, Bachelor Degree in Biotechnology, Università degli Studi di Ferrara, Italy
  • 03/20 - 06/20: Tutor of Physics I, Bachelor Degree in Geology, Università degli Studi di Ferrara, Italy



  • 11/2022 - present: Research Associate, Cardiff University, UK


  • 11/2019 - 3/2023: PhD in Physics, Università degli Studi di Ferrara, Italy. Supervisor: Dr. Martina Gerbino

  • 04/2018 - 08/2018: Erasmus +, Ruprecht-Karls-Universitaet, Heidelberg, Germany
  • 09/2017 - 09/2019: Master Degree in Physics, Università degli Studi di Padova, Italy. Grade: 110/110 laude

  • 09/2014 - 09/2017: Bachelor Degree in Astronomy, Università degli Studi di Padova, Italy. Grade: 110/110 laude