Cosmic Dawn at High Latitudes Conference

Session

Session 4

25 Jun 2024, 13:30

Beijer auditorium (Swedish Royal Academy of Sciences)

148. The 21cm line from the high-z IGM

Benedetta Ciardi

25/06/2024, 13:30

100. Towards precision constraints on reionization history with quasar IGM damping wings

Timo Kist (Leiden Observatory)

25/06/2024, 14:00

Constraining the Epoch of Reionization remains one of the pivotal tasks of modern cosmology, and next-generation telescopes are opening up the path to the first precision constraints on the timing of reionization derived from the Ly-alpha damping wing signature imprinted on the spectra of high-redshift quasars by the foreground neutral intergalactic medium (IGM). In the coming years, EUCLID...

103. Damping wings in the Lyman-alpha forest, a model-independent measurement of the neutral fraction at 5.4<z<6.1

Dr Benedetta Spina (Heidelberg University)

25/06/2024, 14:15

Recent observations have positioned the endpoint of the EoR at redshift $z \sim 5.3$. However, it has not been possible to discern whether this progression occurred slowly and late, with substantial neutral hydrogen (HI) clouds persisting at redshift $\sim 6$, or rapidly and earlier, driven by the fluctuating UV background, through observations of the Lyman-$\alpha$ forest.

Large-scale...

24. Latest 21cm results from the Murchison Widefield Array

Cathryn Trott (ICRAR - Curtin University)

25/06/2024, 14:30

I will present updates from the past year from the Australian team in the Murchison Widefield Array (MWA) EoR experiment. With over 10 years of data acquired across three different array increments, we have more than a thousand hours of data to analyse. I will discuss the efficient Nextflow pipeline and Quality Assurance metrics developed by the EoR group, and present the latest results from...

6. New Upper Limits of the LOFAR EoR 21 cm Power Spectrum and Their Interpretation

Saleem Zaroubi (Kapteyn Astronomical Institute)

25/06/2024, 14:45

In this talk, I will present the current status of the field and the upper limits results, especially, I will focus on the results from the LOFAR EoR project. I will also discuss the analysis of these data in terms of cosmological models.

110. HERA Phase I and Beyond: Constraints on X-ray heating of the IGM

Steven Murray (Scuola Normale Superiore)

25/06/2024, 15:00

I will discuss the most recent upper limit on the 21cm Power Spectrum from the HERA Collaboration, which used 94 nights of observing with Phase I of the instrument. I will show that these most recent limits are mostly consistent with thermal noise, and represent the deepest limits to date at redshifts 7.9 and 10.4 respectively. I will also touch on the state-of-the-art validation pipeline...

61. HERA bound on x-ray luminosity when accounting for population III stars

Debanjan Sarkar (Trottier Space Institute and Department of Physics, McGill University)

25/06/2024, 15:45

Recently, the Hydrogen Epoch of Reionization Array (HERA) has placed upper bounds on the cosmological 21-cm power spectrum at redshifts $\approx8$ and $10$. These bounds have been instrumental in constraining $L_{\rm X<2 \, keV}/{\rm SFR}$, the soft-band X-ray luminosity per unit star formation rate (SFR). Results suggest that values below $\approx 10^{39.5}\, {\rm erg} \;{\rm s}^{-1} \;{\rm...

74. Capturing the HI 21 cm Signal in Ground-Based Observations Amidst Diverse Systematic Influences

Abhirup Datta (DAASE, IIT Indore)

25/06/2024, 16:00

The Epoch of Reionization (EoR) and Cosmic Dawn (CD) play crucial roles in shaping the early Universe during its initial billion years. Despite their significance, the characteristics of the Intergalactic Medium (IGM) during these epochs remain uncertain and require further observational validation. Current and upcoming radio telescopes, such as EDGES, SARAS, MWA, and SKA, aim to detect the...

56. Study of the diffuse Galactic synchrotron emission using MWA Drift Scan Observations

Samir Choudhuri (Indian Institute of Technology Madras)

25/06/2024, 16:15

The redshifted 21 cm line is an emerging tool in cosmology that helps us understand the large-scale structure of the universe. Drift-scan observations, where the direction in which the telescope's point changes continuously on the sky due to the earth's rotation, provide an economical and stable option if one desires broad sky coverage. However, the Galactic and extra-galactic foreground...

66. Constraining the clustering and 21-cm signature of radio galaxies at cosmic dawn

Sudipta Sikder (Tel Aviv University)

25/06/2024, 16:30

Several ongoing and upcoming radio telescopes are aiming for a detection of either the all sky-averaged (global) 21-cm signal or the 21-cm power spectrum. The extragalactic radio background, as detected by ARCADE-2 and LWA-1, can significantly affect the cosmological 21-cm signal. Such a radio background could have been produced by high-redshift galaxies. We perform a complete calculation that...

153. Discussion

Benedetta Ciardi, Dan Stark

25/06/2024, 16:45