INPA

INPA Seminar - Chiara Capelli (University of Zurich)
2020-02-21 12:00 - 13:00 (America/Los_Angeles) | 50A-5132- Sessler, 50A-5132 Sessler Conference Room, CA
Speaker: Chiara Capelli (University of Zurich)
Title: Data analysis at high-energies for the XENON1T experiment and light calibration system of XENONn
Abstract: The XENON1T experiment searches for Weakly Interacting Massive Particles (WIMPs) with a dual-phase xenon Time Projection Chamber (TPC). To extend its physics reach, the efforts of the XENON collaboration are directed toward exploring other detection channels. For this purpose, considerable work on the signal reconstruction and data analysis has been done to extend the available energy range up to 3\,MeV, two orders of magnitude higher than the standard WIMP analysis. This would allow one to search for the neutrinoless double beta decay (0$
ubetabeta$) of $^{136}$Xe, which is fundamental to probing the Majorana nature of neutrinos and solving the hierarchy problem. The achievements and future prospects for the high-energy analysis with dual-phase TPCs will be presented. Furthermore, the upcoming XENONnT experiment, an upgrade of XENON1T with a larger TPC and reduced background, is expected to start taking data in 2020. Its main goal is to increase the sensitivity to WIMPs by an order of magnitude compared to the current best limit, as well as improving the search for 0$
ubetabeta$. An overview of the new systems, with attention on the light calibration of the 494 photomultiplier tubes (PMTs) will be also presented.

Special INPA SEMINAR - Wouter Van De Pontseele (Harvard/Oxford)
2020-02-19 15:30 - 16:30 | 50A-5132- Sessler, 50A-5132 Sessler Conference Room, CA
Speaker: Wouter Van De Pontseele (Harvard/Oxford)

Title: The MicroBooNE Neutrino Experiment at Fermilab

Abstract: MicroBooNE is a liquid argon time projection chamber in the Booster Neutrino Beam at Fermilab. The technology provides high-resolution imaging of neutrino interactions leading to low-threshold event reconstruction with full angular coverage. As such, this is an ideal place to probe neutrino-argon interactions in the hundreds-of MeV to few-GeV energy range. This talk presents a start-to-end overview demonstrating the physics capabilities of the detector. I will talk about cosmic ray measurement and characterisation, our dominant background.
Furthermore, I will describe the flavour-agnostic neutrino pre-selection, based on the combination of the charge collected by the TPC and the optical information form the PMT system. An overview of recent measurements of neutrino interactions in MicroBooNE, including inclusive charged-current interactions, will be given. I will conclude summarising the ongoing efforts towards our first low-energy-excess results, demonstrating our capability to identify electron neutrinos.

Speaker: Vishal Gajjar (UC Berkeley)
2020-02-14 12:00 - 13:00 | 50A-5132- Sessler, 50A-5132 Sessler Conference Room, CA
Title: Breakthrough Listen’s search for intelligent life in the Universe

Abstract: The discovery of the ubiquity of habitable extrasolar planets, combined with revolutionary advances in instrumentation and observational capabilities, have ushered in a renaissance in the millennia-old quest to answer our most profound question about the Universe and our place within it – Are we alone? The Breakthrough Listen Initiative announced in July 2015 as a 10-year 100M USD program is the most comprehensive effort in history to quantify the distribution of advanced, technologically capable life in the universe. In this talk, I outline the status of the on-going observing campaign with our primary observing facilities, as well as planned activities with these instruments over the next few years. I will also talk about collaborative facilities which will conduct searches for technosignatures in either primary observing mode or commensally. I will highlight some of the novel analysis techniques we are bringing to bear on multi-petabyte data sets, including machine learning tools we are deploying to search for a broader range of technosignatures than was previously possible. https://arxiv.org/abs/1907.05519

INPA Seminar - Harikrishnan Ramani (LBNL)
2020-02-07 12:00 - 13:00 | 50A-5132- Sessler, 50A-5132 Sessler Conference Room, CA
Speaker: Harikrishnan Ramani (LBNL)

Title: Nuclear Isomers as Dark Matter accelerators
Abstract: Weak-scale dark matter particles, in collisions with nuclei, can mediate transitions between different nuclear energy levels. In particular, owing to sizeable momentum exchange, dark matter particles can enable de-excitation of nuclear isomers that are extremely long lived with respect to regular radioactive decays. In this paper, we utilize data from a past experiment with $^{rm 180m}$Ta to search for $gamma$-lines that would accompany dark matter induced de-excitation of this isomer. Non-observation of such transitions above background yields the first direct constraint on the lifetime of $^{rm 180m}$Ta against DM-initiated transitions: $T_{1/2}>1.3times 10^{14}$~a at 90% C.I. Using this result, we derive novel constraints on dark matter models with strongly interacting relics, and on models with inelastic dark matter particles. Existing constraints are strengthened by this independent new method. The obtained limits are also valid for the Standard Model $gamma$-decay of
uc{Ta}{rm 180m}.

Special INPA SEMINAR - Karthik Ramanathan (University of Chicago)
2020-02-04 11:00 - 12:00 | 50A-5132- Sessler, 50A-5132 Sessler Conference Room, CA
Speaker: Karthik Ramanathan (University of Chicago)

Title: Dark Matter Taking Selfies: The DAMIC Experiment

Abstract: The DAMIC (Dark Matter in CCDs) experiment uses silicon charge-coupled devices (CCDs), traditionally employed for imaging purposes, to detect potential ionization signals from dark matter interactions. These approx. mm thick devices feature an impressively low leakage current (< 10-21 A/cm2) and a very low energy threshold (40 eVee), making them ideal low-mass dark matter detectors. In addition, their unique spatial resolution provides for effective identification and mitigation of environmental backgrounds. In this talk, I will highlight recent dark matter-electron scattering limits from the experiment at SNOLAB, discuss the kg-size next generation DAMIC-M detector funded for operation, and show results from “Skipper”instrumented CCDs – a novel readout technique that allows for counting of individual charges, with a demonstrated resolution of 0.07 e-, which ushers in a new era of sensitivity to low-energy interactions.

Speaker: Ann-Kathrin Schutz - Eberhard Karls University of Tubingen
2020-01-31 12:00 - 13:00
Title: Full analysis of the background for the search of neutrinoless double beta decay in Gerda

Abstract: The GERmanium Detector Array (Gerda) experiment aims for the discovery of neutrinoless double beta decay (0νββ) decay in 76Ge. It uses HPGe detectors enriched in the isotope 76Ge, which are directly immersed into liquid argon (LAr). In second phase (Phase II) of Gerda, the radio-pure cryogenic liquid acts not only as cooling medium for the detectors and passive shielding but also as active shielding. Phase II started data taking in Dec 2015 with the design goal of increasing the sensitivity to T 0ν1/2 = O1026 yr by reducing the background by one order of magnitude. Due to the active veto system detecting LAr scintillation light, the superior energy resolution and an improved background recognition, the initial release of Phase II already showed a background rate in the energy region of interest (ROI), after pulse shape discrimination (PSD) and liquid argon veto cuts, in the range of a few counts/(ROI·ton·yr). This made Gerda the first 0νββ experiment being background free up to its design exposure of 100 kg·yr. With the latest data release in mid 2018, comprising a total exposure of 82.4 kg·yr, Gerda remained in the background free regime and it is the first experiment to surpass a median sensitivity on the half-life of 1026 yr for 0νββ decay.
In this talk, a full analysis of the background is presented where all available information on the background has been incorporated in order to develop a detailed background model describing the decomposition of the measured energy spectrum. For the first time, the single- and two-detector data have been combined in a multivariate Bayesian fit approach. Additionally, the background model focuses further on two prominent features in the energy spectrum: the α events dominating the high energy part of the spectrum and the count rates of the potassium γ-lines at 1525 keV and 1461 keV. Thanks to the granularity of the detector array, a study of the coincident events in the two-detector data which can provide further information regarding the location of contaminations has been integrated. Using the background model, important information on the main sources and their locations contributing to the background around
the Q-value of the decay (Qββ) can be deduced. Besides, the spectral shape of the total background around Qββ can be extracted. Both are crucial input informations for reliable results on the 76Ge 0νββ signal search.

Speaker: Jiamin Hou - Max-Planck - Institute for Extraterrestrial Physics
2020-01-24 12:00 - 13:00
Title: Clustering measurements in the final eBOSS quasar sample and their cosmological implications
Abstract:In this talk I present the clustering analysis of the final extended Baryon Oscillation Spectroscopic Survey (eBOSS) quasar sample at redshift 0.8<z<2.2, which bridges the redshift gap between the eBOSS LRG and Lyman-alpha measurements. Mapping the evolution of the expansion and growth of structure histories of our Universe provides us with a crucial test of the standard LCDM cosmological scenario. Our analysis includes a detailed modelling of the impact of the non-linear evolution of density fluctuations, bias, and redshift-space distortions on the two-point correlation function. Using numerical simulations designed to reproduce the uniqueness of the quasar sample, we perform extensive validation tests to characterise potential systematic errors induced by theoretical and observational effects. The constraints obtained from anisotropic clustering measurements can be used to test models of gravity on large-scales. However, these tests require the validation of our analysis techniques in modified gravity scenarios. I present an example of such tests, based on large numerical simulations of standard and modified gravity models to measure galaxy clustering in redshift space.

Speaker: Arnaud De Mattia - IRFU, CEA, Université Paris-Saclay
2020-01-17 12:00 - 13:00
Title: The extended Baryon Oscillation Spectroscopic Survey: clustering measurements, lessons, and prospects
Abstract: In this talk, I will present the clustering analysis of the ELG (Emission Line Galaxy) sample from the eBOSS (extended Baryon Oscillation Spectroscopic Survey) program of the Sloan Digital Sky Survey and review the other clustering analyses of the eBOSS program, dedicated to Luminous Red Galaxies and Quasars. I will discuss theoretical, observational and analysis systematics, how they were estimated and mitigated, focusing on the improvements over the last release of the BOSS program in 2016. Specifically, I will start by presenting the extensive work of the eBOSS collaboration to test model predictions against N-body simulations. The different observational systematics of the eBOSS samples will be reviewed, as well as the adopted correction schemes and the new analysis techniques used to mitigate residual systematics. Different analysis assumptions and their impact on the clustering signal will be discussed. After a review of eBOSS legacy cosmological measurements, I will finish by drawing lessons and prospects for future galaxy surveys.

Speaker: Samuel Hinton - University of Queensland
2020-01-10 12:00 - 13:00
Title: Challenges and pathways forward in supernova cosmology
Abstract: Using the DES photometric supernova cosmology analysis as groundwork, I will summarise our current analysis methodologies, from simulations, to transient classification, selection effect treatment, and cosmology. Despite recent improvements in analysis methods, there still exist fundamental challenges in areas spanning the initial empirical SN Ia model all the way to failing approximations built into cosmology fitters. I will highlight potential solutions to these challenges, to allow the next generation of surveys to lower the systematic floor and provide improved cosmological constraints. Additionally, I will also summarise my BAO and pipeline work for surveys like DESI, and discuss ways I’ve improved scientific workflow to allow more efficient use of researcher time.

Speaker: Suk Sien Tie - Ohio State University
2019-12-06 12:00 - 13:00
Title: Cosmology with the Lya forest: beyond two-point statistics, DESI instrumentation
Abstract: The Lyman-alpha forest is currently the only probe of cosmology and the state of the intergalactic medium (IGM) between redshifts of z=2 and 6. It’s higher-order clustering, specifically its three-point correlation function (3PCF), contains information that can help to constrain fluctuations in the ionizing background and temperature fields of the IGM, thus providing a novel way to constrain their effects on cosmological analyses of the LyA forest. In this talk, I will present theoretical predictions of the 3PCF of the LyA forest, considering both a uniform and spatially varying UV background. I will discuss the exciting possibilities that future surveys like DESI will enable in this area. Finally, I will present my instrumentation work on the DESI sky camera and the fiber positioner anti-collision algorithm, and how they facilitate the DESI survey to achieve its science goals.

Speaker: Chirag Modi - University of California, Berkeley
2019-11-22 12:00 - 13:00
Title: Reconstruction of Cosmological Fields in Forward Model Framework – Galaxy Clustering and Intensity Mapping
Abstract:
In this talk, I will outline the forward model approach to reconstruct cosmological fields in a Bayesian framework. I will focus on two examples – galaxy clustering and neutral hydrogen intensity mapping.
In galaxy clustering example, I will use the observations of galaxy surveys to reconstruct the initial Lagrangian field.
Here, we develop a novel framework with neural networks to forward model halo masses and positions and demonstrate that our method outperforms standard reconstruction in both real and redshift space.
This reconstructed initial field has enhanced signal for baryon acoustic oscillations and can enhance science returns for surveys like DESI.
For neutral hydrogen surveys, we lose over 50% of the modes at high redshifts due to foregrounds and it severely hampers their feasibility for cosmological analysis.
With a novel bias framework for the forward model, I will show that we are able to reconstruct over 90% of these modes and this recovers cross-correlations with photo-z surveys like LSST and tracers like CMB lensing. Lastly, I will briefly touch upon assumptions made in this reconstruction framework regarding noise models and likelihood. I will discuss preliminary ways to improve upon them using deep learning.

Speaker: Solène Chabanier - IRFU, CEA, Université Paris-Saclay
2019-11-08 12:00 - 13:00
The title and abstract are forthcoming.

Speaker: Katherine Rawlins - University of Alaska at Anchorage
2019-10-25 12:00 - 13:00

Speaker: Mattia Beretta - Development & Application of Scintillation Detectors for Rare Events Searches
2019-10-11 12:00 - 13:00

Speaker: Daniel Whiteson - What has the Machine Learned?
2019-10-04 12:00 - 13:00 | INPA Common Room, 50-5026

Will Thompson - COSINE-100 (Yale)
2019-07-12 12:00 - 13:00
TBA

Adam Bernstein (LLNL) - The Watchman Experiment
2019-06-28 12:00 - 13:00 | 50A-5132- Sessler, 50A-5132 Sessler Conference Room, CA

Vid Irsic (UW) - Lyman-alpha forest
2019-05-24 12:00 - 13:00 | 50A-5132- Sessler, 50A-5132 Sessler Conference Room, CA

Ben Land (UCB) - Solar neutrinos with SNO, SNO+, and Beyond
2019-05-17 12:00 - 13:00 | 50A-5132- Sessler, 50A-5132 Sessler Conference Room, CA
This seminar gives a brief historical introduction to solar neutrino detection, and motivates the use of solar neutrinos as a tool to probe physics beyond the standard model. An analysis of SNO data constraining the lifetime of neutrino decay is presented, along with solar neutrino results from SNO+ water phase. Additionally, R&D for simultaneous detection of Cherenkov and scintillation light in future solar neutrino experiments is discussed, with a first look at single photon detection characteristics of LAPPDs.

NO INPA SEMINAR MTG
2019-05-10 12:00 - 13:00 | INPA Common Room, 50-5026

Maria Simanovskaia (UCB) - Searching for Dark Matter Axions with HAYSTAC
2019-05-03 12:00 - 13:00 | 50A-5132- Sessler, 50A-5132 Sessler Conference Room, CA
Continuing on the topic of axion searches from last week, this seminar will highlight one experiment, HAYSTAC, which looks for an axion-induced power excess spectrally coincident with the resonance of a microwave cavity immersed in a strong magnetic field. This is the first such experiment to incorporate a dilution refrigerator and Josephson parametric amplifier and thereby achieve near-quantum-limited noise performance. Results will be discussed, as well as planned upgrades and research and development work for the future.

Karl van Bibber (UCB) - A Primer on the Axion
2019-04-26 12:00 - 13:00 | 50A-5132- Sessler, 50A-5132 Sessler Conference Room, CA
This is the first of a two-part series on the axion and the current experimental campaign to find it. This first seminar will focus on the history and motivation of the axion, rooted in the Strong-CP problem, i.e. the absence of the neutron electric dipole moment, some phenomenology, and an overview of experimental avenues to detect the axion. In the second part next week, by Maria Simanovskaia, one particular experiment, HAYSTAC will be presented in detail, which searches for the axion as the dark matter of the universe.

NO INPA SEMINAR MTG
2019-04-19 12:00 - 13:00, 2019-03-15 12:00 - 13:00, 2019-03-08 12:00 - 13:00 | 50A-5132- Sessler, 50A-5132 Sessler Conference Room, CA

NO INPA SEMINAR MTG
2019-04-12 12:00 - 13:00

SPECIAL - Rajesh Sankaran - (ANL) - Waggle and Array of Things
2019-04-08 10:30 - 11:30 | 50-Auditorium
The Waggle Platform is a research project at Argonne National Laboratory to
design, develop, and deploy a novel wireless sensor platform with advanced edge
computing capabilities to enable a new breed of sensor-driven environmental
science and smart city research. The software and hardware designs from the
Waggle project are used by the NSF funded Array Of Things, which is building
a smart city and open data with urban sensors in Chicago. The innovative
architecture leverages emerging technology in low-power processors, sensors,
and cloud computing to build powerful and reliable sensor nodes that can
actively analyze and respond to data. Cloud computing provides elastic resources
for storing and computing on data. Waggle is designed from the ground up with
security, privacy, extensibility, and survivability as key design points. The
Waggle reference platforms and software are launching points. All of the
software is Open Source, and the software is modular, so researchers can add
their own sensors, computing pipelines, and data analysis. The talk will discuss
the various technical aspects of the Waggle platform and the Array of Things
urban deployment.

Giovanni Benato (UCB, LBL) - Waiting for neutrinoless double beta decay with cryogenic calorimeters
2019-04-05 12:00 - 13:00 | 50A-5132- Sessler, 50A-5132 Sessler Conference Room, CA
Neutrinoless double beta decay is the matter-creating process that is most accessible with the current technology.
Its discovery would demonstrate the non-conservation of lepton number and that neutrinos have a Majorana mass component, and indicate a possible solution for the baryon asymmetry of the universe.
In this seminar, I will review the current status of the search for neutrinoless double beta decay,
discussing the recent developments of models for the calculation of nuclear matrix elements,
and the various possible mechanisms contributing to the process.
In addition, I will report on the current status of the CUORE experiment for the search of neutrinoless double beta decay with cryogenic calorimeters, and on the plans for its upgrade, CUPID.

Morgan Askins (UCB) - Search for invisible nucleon decay in the SNO+ detector
2019-03-29 12:00 - 13:00 | 50A-5132- Sessler, 50A-5132 Sessler Conference Room, CA
Many Grand Unified Theories predict processes that would allow baryons to decay to leptons, violating baryon number conservation. The observation of baryon number violation in nucleon decay would be a revelation as well as being pivotal in understanding the apparent asymmetry between baryons and anti-baryons in the universe. This is manifest in some theories primarily through the decay of nucleons to three chargeless leptons (e.g. n to 3 neutrino), which can only be observed through the resulting nuclear deexcitation gamma. This “invisible” nucleon decay could be observable in water through the deexcitation of the resulting oxygen-15 nucleus which emits a 6.2 MeV gamma and requires that backgrounds at these energies, in a large detector, to be extremely low. Presented here are the first results from the SNO+ light water phase which consists of nearly 120 days of live data taking. A blind analysis was performed using a Poisson counting method and a maximum likelihood method independently to obtain the results.

Aaron Manalaysay (UC Davis) - 178 nm: The magic of liquid xenon and the search for dark matter
2019-03-22 12:00 - 13:00 | 50A-5132- Sessler, 50A-5132 Sessler Conference Room, CA
The introduction of liquid-xenon (LXe) to the field of dark-matter direct detection caused a paradigm shift in this search. Primarily focused on the search for the Weakly Interacting Massive Particle, LXe detectors have improved our sensitivity to these dark-matter candidates by a factor of 10,000 since their introduction roughly ten years ago, compared to the factor of 50 sensitivity improvement that the field had covered in the twenty years before that. The rapid pace at which LXe detectors have pushed the field is due in part to their ability to scale to arbitrarily large size, thereby drastically reducing the rates of background signals in these rare-event searches. Though these detectors have seen tremendous successes, each result has been accompanied by its own set of challenges to be overcome, which will also be true for the next generation experiments. I will describe the most recent such U.S.-based experiment, LUX, and highlight the key innovative analyses that led to its impressive results. I will extend the discussion to cover LUX’s upcoming LBL-led successor, LZ, which will be sensitive to WIMP-nucleus interactions as rare as roughly 0.5 events/kg/millennium. Time permitting, I will expand the view by discussing the ways in which LXe is a powerful tool for probing non-WIMP dark-matter candidates.
