Dear colleagues,

This is a reminder for the first CosKASI Early Career Researcher seminar of the semester at 4:00 PM KST on Thursday (March 9) by Alba Kalaja from the Van Swinderen Institute.

Please find the title, abstract and zoom details below and also on our webpage. Previous talks in the series can also be found on our youtube channel. Please feel free to forward this email to your colleagues who might be interested in this talk.

Best wishes,
CosKASI ECR seminar organizing committee

Title: The reconstruction of the CMB lensing bispectrum

Abstract:

Weak gravitational lensing by the intervening large-scale structure (LSS) of the Universe is the leading non-linear effect on the anisotropies of the cosmic microwave background (CMB). The integrated line-of-sight gravitational potential that causes the distortion can be reconstructed from the lensed temperature and polarization anisotropies via estimators quadratic in the CMB modes. While previous studies have focused on the lensing power spectrum, upcoming experiments will be sensitive to the bispectrum of the lensing field, sourced by the non-linear evolution of structure. The detection of such a signal would provide additional information on late-time cosmological evolution, complementary to the power spectrum. However, the reconstruction process introduces a number of noise biases that significantly hinder the signal. Identifying these terms represents a first step towards detection. In this talk, I will discuss how we compute the leading noise biases of the bispectrum in the flat-sky limit, and how these results compare to simulations.

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Meeting ID: 883 3749 7977
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---------- Forwarded message ---------
From: CosKASI <coskasi2020@gmail.com>
Date: Thu, Feb 16, 2023 at 9:42 AM
Subject: Announcement of the CosKASI ECR seminar series - semester 1, 2023

Dear colleagues,

We are excited to announce that the CosKASI Early Career Researcher seminar series will resume this semester. Since its launch in 2021, the seminar series has brought forward fascinating works of 32 early-stage researchers around the world. We currently have 8 talks upcoming.

The talks will start on Thursday 9th March at 16:00 KST and run every two weeks. Each talk will be about 45 minutes long followed by 15 minutes reserved for questions. A detailed schedule and individual abstracts of the seminar talks are provided on our website: http://cosmology.kasi.re.kr/seminar.php?year=ECR. Please see below the title and abstract for our first talk. 

If you are not already on our mailing list and would like to be informed about upcoming talks, please sign up by sending an email to coskasi2020@gmail.com.You may also want to check out our youtube channel, where recordings of our previous talks have been uploaded.

Please forward this email to any colleagues who might be interested in the seminar series.

Best wishes,

The CosKASI ECR seminar organising committee

Time: September 1st at 16:00 KST

Speaker: Alba Kalaja (VSI Groningen)

Title: The reconstruction of the CMB lensing bispectrum

Abstract:

Weak gravitational lensing by the intervening large-scale structure (LSS) of the Universe is the leading non-linear effect on the anisotropies of the cosmic microwave background (CMB). The integrated line-of-sight gravitational potential that causes the distortion can be reconstructed from the lensed temperature and polarization anisotropies via estimators quadratic in the CMB modes. While previous studies have focused on the lensing power spectrum, upcoming experiments will be sensitive to the bispectrum of the lensing field, sourced by the non-linear evolution of structure. The detection of such a signal would provide additional information on late-time cosmological evolution, complementary to the power spectrum. However, the reconstruction process introduces a number of noise biases that significantly hinder the signal. Identifying these terms represents a first step towards detection. In this talk, I will discuss how we compute the leading noise biases of the bispectrum in the flat-sky limit, and how these results compare to simulations.

Join Zoom Meeting
https://us02web.zoom.us/j/88337497977?pwd=cSs5ZUdQWEJHRkRtemRKZllsR0ZaUT09

Meeting ID: 883 3749 7977
Passcode: 550352
One tap mobile
+82261054111,,88337497977# Korea, Republic of
+82260222322,,88337497977# Korea, Republic of
Dial by your location
        +82 2 6105 4111 Korea, Republic of
        +82 2 6022 2322 Korea, Republic of
Meeting ID: 883 3749 7977

Find your local number: https://us02web.zoom.us/u/kdHxfgU4b