Reionization on a Blackboard

Sep 19, 2022, 8:30 AM → Sep 22, 2022, 6:00 PM America/New_York

Alpha/Beta (MfA)

We are pleased to announce the Reionization on a Blackboard workshop, which will take place at the Center for Computational Astrophysics (CCA) in New York City from September 19-22, 2022.

The aim of this 4-day workshop is to discuss four timely topics at the forefront of current research on the Epoch of Reionization. The meeting will move away from the traditional format of a series of talks, in an effort to maximize interactions and foster collaborations among the attendees.

Each day of the workshop will focus on particular topics with structured morning sessions and unstructured parallel discussion sessions in the afternoon. Together we will attempt to tackle the following four topics and open questions:

1. What will the JWST teach us about the sources that drive reionization and the high redshift intergalactic medium?
2. What can we expect to learn about reionization from upcoming, near-future redshifted 21 cm, cosmic microwave background, and line-intensity mapping observations?
3. What can we learn from different approaches to reionization modeling? Are there important missing ingredients in these models?
4. What do current observations of the Lyman-alpha forest imply about reionization? Have we reached a consensus view? What more can we hope to learn from the forest in the future? 

We particularly encourage applications from graduate students and junior researchers, as well as from historically underrepresented groups in Astronomy.

By attending this workshop, you agree to follow the Flatiron Institute’s code of conduct

Scientific Organizing Committee (SOC):
George Becker, Benedetta Ciardi, Anson D’Aloisio, Sultan Hassan (Chair), Joseph Hennawi, Adam Lidz, Matt McQuinn, Garrelt Mellema, Hy Trac

Local Organizing Committee (LOC):
Cristina Duncan, Abigail Creem, Kristen Camputaro

Attendees:

Aaron Smith	Harvard University
Adam Lidz	University of Pennsylvania
Adrian Liu	McGill University
Andrei Mesinger	Scuola Normale Superiore
Aniket Bhagwat	Max Planck Institute for Astrophysics
Ankita Bera	Presidency University
Anna Schauer	The University of Texas at Austin
Anson D'Aloisio	University of California, Riverside
Anthony Pullen	New York University
Benedetta Ciardi	Max Planck Institute for Astrophysics
Benedetta Spina	Argelander-Institut für Astronomie
Bradley Greig	The University of Melbourne
Caitlin Doughty	Leiden Observatory
Charlotte Mason	Cosmic Dawn Center, Niels Bohr Institute
Christopher Cain	University of California, Riverside
Cody Carr	University of Minnesota
Enrico Garaldi	Max-Planck-Institut fuer Astrophysik
Floriane Leclercq	University of Texas at Austin
Francisco Villaescusa-Navarro	Flatiron Institute
Frederick Davies	Max Planck Institute for Astronomy
George Becker	University of California, Riverside
Giulio Fabbian	Center for Computational Astrophysics
Guochao (Jason) Sun	Northwestern University
Hannah Fronenberg	McGill University
Holly Christenson	University of California, Riverside
Huanqing Chen	Canadian Institute for Theoretical Astrophysics
Jennifer Yik-Ham Chan	Canadian Institute for Theoretical Astrophysics and University of Toronto
Kai-Feng Chen	Massachusetts Institute of Technology
Keir Rogers	University of Toronto
Kirit Karkare	University of Chicago/Fermilab
L. Y. Aaron Yung	NASA Goddard Space Flight Center
Laura Keating	University of Edinburgh
Lichen Liang	Canadian Institute for Theoretical Astrophysics
Lily Whitler	University of Arizona
Lucia Perez	Princeton University
Luz Ángela García Peñaloza	Universidad ECCI
Maximilien Franco	University of Texas
Michael Pagano	McGill University
Molly Wolfson	University of California, Santa Barbara
Mosima Masipa	University of the Western Cape
Olivia Cooper	The University of Texas at Austin
Rahul Kannan	Harvard University
Ryan Endsley	The University of Texas at Austin
Sarah Bosman	Max Planck Institute for Astronomy, Heidelberg
Steven Finkelstein	The University of Texas at Austin
Suk Sien Tie	University of California, Santa Barbara
Sultan Hassan	Flatiron Institute
Wichahpi King	University of Texas at Austin
Yongda Zhu	University of California, Riverside
Yu-Heng Lin	University of Minnesota
Patrick Breysse	New York University

Monday, September 19

8:30 AM Breakfast / Check-in

Blackboard Talk(s): Steve Finkelstein and Charlotte Mason (Part I)

1 What will the JWST teach us about the sources that drive reionization and the high redshift intergalactic medium?

10:30 AM Break

Blackboard Talk(s): Steve Finkelstein and Charlotte Mason (Part II)

2 What will the JWST teach us about the sources that drive reionization and the high redshift intergalactic medium?

12:00 PM Lunch

3 Parallel Session

1- Prospects for constraining Reionization History with the Ly-alpha Line: Transmission Statistics, Clustering, or other methods.
2- What are the most promising techniques for constraining Lyman-continuum escape from high-z galaxies?
3- Calibrating the relationship between galaxy properties and ionizing photon production.
4- Reaching for zero metallicity: what will we learn from JWST about Population III stars, the production of metals in galaxies, and the enrichment of the IGM.

2:45 PM Break

Reporting Back

Reception: 5:00-6:00: Bar Area Reception "Cocktail Hour" 6:00-8:00: Seated Dinner in Amici Room

details to follow

Tuesday, September 20

8:30 AM Breakfast / Check-in

Blackboard Talk(s): (Sarah Bosman and Laura Keating (Part I))

4 What do current observations of the Lyman-alpha forest imply about reionization? Have we reached a consensus view? What more can we hope to learn from the forest in the future?

10:30 AM Break

Blackboard Talk(s): (Sarah Bosman and Laura Keating (Part II))

5 What do current observations of the Lyman-alpha forest imply about reionization? Have we reached a consensus view? What more can we hope to learn from the forest in the future?

12:00 PM Lunch

6 Parallel Session

1- How robust is the evidence for reionization ending as late as z~5? Have we found a smoking gun for late reionization?

2- How consistent are models of patchy reionization with late-time (z < 5.5) constraints from Lyman-alpha down to the Lyman continuum? How can these constraints be improved and how would they inform reionization models?

3- What new opportunities will come from spectra of the highest-redshift (z >~ 7) QSOs, including those found in upcoming surveys? How robust will the constraints be for the neutral fraction, metal enrichment, etc?

4- What are the best opportunities for combining Lyman-series absorption with other observations? What can we constrain?

2:45 PM Break

Reporting Back

Lightning Talks

Wednesday, September 21

8:30 AM Breakfast / Check-in

Blackboard Talk(s): Benedetta Ciardi and Anson D’Aloisio (Part I)

7 What can we learn from different approaches to reionization modeling? Are there important missing ingredients in these models?

10:30 AM Break

Blackboard Talk(s): Benedetta Ciardi and Anson D’Aloisio (Part II)

8 What can we learn from different approaches to reionization modeling? Are there important missing ingredients in these models?

12:00 PM Lunch

9 Parallel Session

1- Machine learning methods in reionization modeling and data analysis/inference. How can AI/ML tools (e.g. gaussian processes, convolutional neural networks, generative adversarial networks, graphs, symbolic regression) be used to improve theoretical modeling and data analysis/inference?

The next three topics are meant to connect theoretical modeling to observations by answering questions like: Have we extracted all the available information from existing observations to constrain models? Which (ideal) observations would we like to have? Are our models appropriate to correctly interpret observations?

2- Modeling high-z galaxies. Example topics include: Are the modeling techniques appropriate for interpreting the observations correctly? Do different modeling techniques lead to different inferences? Are there important missing ingredients in existing models which may bias inferences? Are there ambiguities in comparing measured and modeled quantities? Which observations are most informative to modelers? Are the models predictive? Can current simulations model the escape fraction?

3- Modeling QSO absorption spectra. Example topics include: Are the modeling techniques appropriate for interpreting the observations correctly? Do different modeling techniques lead to different inferences? Are there important missing ingredients in existing models which may bias inferences? Are there ambiguities in comparing measured and modeled quantities? Which observations are most informative to modelers? Are the models predictive?

4- Modeling line intensity mapping and the CMB. Are the modeling techniques appropriate for interpreting the observations correctly? Do different modeling techniques lead to different inferences? Are there important missing ingredients in existing models which may bias inferences? Are there ambiguities in comparing measured and modeled quantities? Which observations are most informative to modelers? Are the models predictive?

2:45 PM Break

Reporting Back

Lightning Talks

Thursday, September 22

8:30 AM Breakfast / Check-in

Blackboard Talk(s): (Kirit Karkare and Adrian Liu (Part I))

10 What can we expect to learn about reionization from upcoming, near-future redshifted 21 cm, cosmic microwave background, and line-intensity mapping observations?

10:30 AM Break

Blackboard Talk(s): (Kirit Karkare and Adrian Liu (Part II))

11 What can we expect to learn about reionization from upcoming, near-future redshifted 21 cm, cosmic microwave background, and line-intensity mapping observations?

12:00 PM Lunch

12 Parallel Session

1- What will it take to establish an initial 21 cm detection of either the fluctuating or global signal and convince the community that the measurement is real? Which systematics are most worrisome? How about for other line-intensity mapping (LIM) signals?

2- For interpreting 21 cm/LIM/kSZ measurements, how should we best parameterize our ignorance of the ionizing sources and other relevant, yet uncertain, quantities? How do we incorporate observational constraints into our models and which current/future observations are most useful? Which aspects of 21 cm/LIM/kSZ modeling are least under control?

3- How to best extract the reionization-era kSZ signal and what will we learn from it? How do we separate it from the post-reionization kSZ and other foregrounds?

4- What are the most interesting plausible signatures of dark matter properties in future 21 cm measurements during reionization, cosmic dawn, and the dark ages?

2:45 PM Break

Reporting Back

Happy Hour