Final Report Summary - CIBORIGINS (Exploring the Cosmological Origins of the Cosmic near Infrared Background Fluctuations)
The broad goals of the “CIBorigins” project are to understand the origins of the Cosmic Infrared Background (CIB) and investigate its potential as a cosmological probe with a special focus on the upcoming Euclid Space Telescope. The original objectives are three-fold: 1. to model the CIB signatures from the first stars and black holes, 2. to construct lightcones and mock images for the Euclid mission, and 3. to isolate high-z CIB using gamma-ray data. These goals are considered completed.
The first objective is regarded as completed with two papers published early 2016. First, we established that the currently measured CIB signal is unlikely to originate from the early Universe and special techniques must be employed to extract it. This was the subject of “On the physical requirements for a pre-reionization origin of the unresolved near-infrared background” in Monthly Notices of the Royal Astronomical Society 2016 [1]. This study was followed by a paper “Detecting high-z galaxies in the near-infrared background “ published in the same journal where we explain how the CIB signal from the early Universe can be probed using cross-correlations [2].
We have further published two papers relevant for the second objective. First, we outline the observational requirements for probing the early universe using the James Webb Space Telescope (JWST) in “Reconstructing Emission from Pre-reionization Sources with Cosmic Infrared Background Fluctuation Measurements by the JWST” [3]. Much of the work presented in this paper is also directly applicable to Euclid. Second, we directly investigate the potential of measuring the properties of the early universe in a novel paper “Lyman-tomography of Cosmic Infrared Background Fluctuations with Euclid: Probing Emissions and Baryonic Acoustic Oscillations at z ≳ 10” also appearing in ApJ 2015 [4]. Additionally, we have an accepted paper in press “AKARI Near-Infrared Background Fluctuations Arise from Normal Galaxy Populations” [3] which provides insights into earlier measurements with the AKARI satellite.
As the two-year time frame of the project has come to an end, two investigations are still ongoing. First, a paper presenting the results of CIB investigation with Fermi/LAT data is being prepared for submission [6]. Second, an investigation of new techniques proposed for Euclid using available HST data is currently in progress. This was not among the original proposed tasks but we consider it an important extension of the project. The fellow has secured an extended employment contract with the host institution in order to carry out this research.
The above record shows that we have been successful in following the timeline outlined in the original proposal. To summarize, the fellow has two first-author papers published and another in preparation. Additionally, the fellow has co-authored four papers directly addressing the objectives of the project.
The fellow has integrated well into the European research community and demonstrated productiveness in establishing new collaborations between scientists in Germany, Italy and the Nederlands. The fellow has also participated in Euclid meetings, a large European consortium. The fellow independently organized a scientific conference hosted at the host institution (MPA) in June 2015 with 33 participants from a variety of international institutions (http://wwwmpa.mpa-garching.mpg.de/nirb2015/index.html). A significant transfer-of-knowledge task was achieved with the completion of this successful meeting.
The fellow has also delivered a major part of proposed outreach activities with the launch of an Icelandic Astronomy webpage (www.geimurinn.is) which bring news and educational material tailored to children. This webpage now runs side-by-side with the existing Astronomy webpage for adults (www.stjornufraedi.is). The fellow also participated in the Open Night in Garching, presenting his research to the public.
Resources for the fixed number of researcher-months have been used in accordance with the original research plan. The management of the project has been straight-forward as it involves only one beneficiary (the fellow). No unexpected problems have occurred. Resources have been used in accordance with the research plan. Allowance was used for travel, both for collaboration meetings and international conferences where scientific results were presented. All costs have been pre-approved by the scientist in charge and institute director.
[1] Helgason, K., Ricotti, M., Kashlinsky, A., & Bromm, V. 2016, MNRAS, 455, 282
[2] Yue, B., Ferrara, A., & Helgason, K. 2016a, 458, 4008 MNRAS
[3] Kashlinsky, A., Mather, J. C., Helgason, K., Arendt, R. G., Bromm, V., & Moseley, S. H. 2015b, ApJ, 804, 99
[4] Kashlinsky, A., Arendt, R. G., Atrio-Barandela, F., & Helgason, K. 2015a, ApJ, 813, L12
[5] Helgason, K., Komatsu, E., M. ApJ 2016 (arXiv:1611.00042)
[6] Desai, A., Ajello, M., Omodei, N., Hartmann, D., Dominguez, A., Paliya, V. S., Helgason, K., Finke, J. 2017 (in prep.)
The first objective is regarded as completed with two papers published early 2016. First, we established that the currently measured CIB signal is unlikely to originate from the early Universe and special techniques must be employed to extract it. This was the subject of “On the physical requirements for a pre-reionization origin of the unresolved near-infrared background” in Monthly Notices of the Royal Astronomical Society 2016 [1]. This study was followed by a paper “Detecting high-z galaxies in the near-infrared background “ published in the same journal where we explain how the CIB signal from the early Universe can be probed using cross-correlations [2].
We have further published two papers relevant for the second objective. First, we outline the observational requirements for probing the early universe using the James Webb Space Telescope (JWST) in “Reconstructing Emission from Pre-reionization Sources with Cosmic Infrared Background Fluctuation Measurements by the JWST” [3]. Much of the work presented in this paper is also directly applicable to Euclid. Second, we directly investigate the potential of measuring the properties of the early universe in a novel paper “Lyman-tomography of Cosmic Infrared Background Fluctuations with Euclid: Probing Emissions and Baryonic Acoustic Oscillations at z ≳ 10” also appearing in ApJ 2015 [4]. Additionally, we have an accepted paper in press “AKARI Near-Infrared Background Fluctuations Arise from Normal Galaxy Populations” [3] which provides insights into earlier measurements with the AKARI satellite.
As the two-year time frame of the project has come to an end, two investigations are still ongoing. First, a paper presenting the results of CIB investigation with Fermi/LAT data is being prepared for submission [6]. Second, an investigation of new techniques proposed for Euclid using available HST data is currently in progress. This was not among the original proposed tasks but we consider it an important extension of the project. The fellow has secured an extended employment contract with the host institution in order to carry out this research.
The above record shows that we have been successful in following the timeline outlined in the original proposal. To summarize, the fellow has two first-author papers published and another in preparation. Additionally, the fellow has co-authored four papers directly addressing the objectives of the project.
The fellow has integrated well into the European research community and demonstrated productiveness in establishing new collaborations between scientists in Germany, Italy and the Nederlands. The fellow has also participated in Euclid meetings, a large European consortium. The fellow independently organized a scientific conference hosted at the host institution (MPA) in June 2015 with 33 participants from a variety of international institutions (http://wwwmpa.mpa-garching.mpg.de/nirb2015/index.html). A significant transfer-of-knowledge task was achieved with the completion of this successful meeting.
The fellow has also delivered a major part of proposed outreach activities with the launch of an Icelandic Astronomy webpage (www.geimurinn.is) which bring news and educational material tailored to children. This webpage now runs side-by-side with the existing Astronomy webpage for adults (www.stjornufraedi.is). The fellow also participated in the Open Night in Garching, presenting his research to the public.
Resources for the fixed number of researcher-months have been used in accordance with the original research plan. The management of the project has been straight-forward as it involves only one beneficiary (the fellow). No unexpected problems have occurred. Resources have been used in accordance with the research plan. Allowance was used for travel, both for collaboration meetings and international conferences where scientific results were presented. All costs have been pre-approved by the scientist in charge and institute director.
[1] Helgason, K., Ricotti, M., Kashlinsky, A., & Bromm, V. 2016, MNRAS, 455, 282
[2] Yue, B., Ferrara, A., & Helgason, K. 2016a, 458, 4008 MNRAS
[3] Kashlinsky, A., Mather, J. C., Helgason, K., Arendt, R. G., Bromm, V., & Moseley, S. H. 2015b, ApJ, 804, 99
[4] Kashlinsky, A., Arendt, R. G., Atrio-Barandela, F., & Helgason, K. 2015a, ApJ, 813, L12
[5] Helgason, K., Komatsu, E., M. ApJ 2016 (arXiv:1611.00042)
[6] Desai, A., Ajello, M., Omodei, N., Hartmann, D., Dominguez, A., Paliya, V. S., Helgason, K., Finke, J. 2017 (in prep.)