LBNL Physics Division Research Progress Meetings

Michael Hance (UCSC) "Searching for Compressed SUSY at the Energy Frontier"
2018-05-31 16:00 - 17:00 (America/Los_Angeles)
ABSTRACT:
Weak-scale Supersymmetry can help to resolve several puzzles presented by the Standard Model, including the nature of dark matter and the naturalness of the Higgs mass, and has motivated a robust search program at the Large Hadron Collider. Searches for direct production of Supersymmetric partners of weak bosons and leptons are particularly interesting as probes of dark matter and naturalness, but are challenged by small cross sections, low-momentum decay products, and multiple Standard Model backgrounds. I will review efforts by the ATLAS experiment to discover such new particles, with an emphasis on scenarios with “compressed” mass spectra containing nearly-mass-degenerate states. I will discuss recent LHC results, as well as prospects for discovery in Run 2 and beyond.

Masashi Hazumi (KEK) "LiteBIRD Satellite for Tests of Cosmic Inflation and Quantum Gravity"
2018-06-04 14:00 - 15:00 | HYBRID 50A-5132 (Sessler Conference Room), https://lbnl.zoom.us/j/91782268585, 50A-5132
Abstract:
Cosmological inflation is the leading hypothesis to resolve the problems in the Big Bang theory.
It predicts that primordial gravitational waves were created during the inflationary era, which
then imprinted large-scale curl patterns in the cosmic microwave background (CMB)
polarization map called the B-modes.
Measurements of the CMB B-mode signals are known as the best probe
to detect the primordial gravitational waves.
LiteBIRD is a candidate for JAXA’s strategic large mission to map the polarization of
the CMB radiation over the full sky at large angular scales with unprecedented precision,
which will offer us a crucial test of cosmic inflation. It will also serve as the first crucial test of
quantum gravity such as superstring theory. Precise polarization maps of LiteBIRD will also
provide us with valuable pieces of information on particle physics and astrophysics.
In this talk, I will give an overview of the science and design of LiteBIRD

Norbert Zacharias (USNO) "Impact of Gaia on Astrometry and Beyond"
2018-06-14 16:00 - 17:00 | INPA Common Room (50-5026), 50-5026
April 2018 marks the 2nd data release (DR2) of the ESA Gaia space mission.
A new era in astrometry begun. Accurate positions, proper motions
and parallaxes for over a billion stars are now available on the
sub-mas level. The properties of DR2 will be explained in context
to pre-Gaia data and the final Gaia results expected in a few years.
The impact of Gaia reaches far into almost all of astronomy, and a
few examples will be given.

Joshua Spitz (U. Michigan) " First Measurement of Monoenergetic Muon Neutrino Charged Current Interactions
2018-06-21 08:00 - 17:00 | HYBRID 50A-5132 (Sessler Conference Room), https://lbnl.zoom.us/j/91782268585, 50A-5132
ABSTRACT:
This talk will present the first measurement of monoenergetic muon
neutrino charged current interactions. The MiniBooNE experiment at
Fermilab has been used to isolate and study 236 MeV muon neutrino
events originating from charged kaon decay at rest. The muon
kinematics and total cross section have been extracted from this data.
Notably, this result is the first known-energy, weak-interaction-only
probe of the nucleus to yield a measurement of omega (energy
transferred to the nucleus) using neutrinos, a quantity thus far only
accessible through electron scattering. I will discuss the
significance of this measurement, and these monoenergetic neutrinos in
general, for elucidating both the neutrino-nucleus interaction and
oscillations.
Slides here

Adam Becker (UCB) "An Incomplete Survey of Proposed Solutions to the Quantum Measurement Problem"
2018-06-28 16:00 - 17:00 | HYBRID 50A-5132 (Sessler Conference Room), https://lbnl.zoom.us/j/91782268585, 50A-5132
ABSTRACT:
The central puzzle that drives the field of quantum foundations is the measurement problem: what gives rise to the appearance of wave function collapse? While there is no single answer to this question that has wide acceptance, this is not for lack of available options. A variety of solutions to the measurement problem have been proposed, in the form of various interpretations or modifications of quantum mechanics. Some solutions eliminate collapse entirely, as in the many-worlds and de Broglie-Bohm interpretations. Others propose altering the dynamics of the theory to make collapse objective, as in GRW (stochastic collapse) and gravitational collapse theories. “Psi-epistemic” interpretations attempt to dissolve the measurement problem by claiming that the wave function isn’t something real in itself, but merely a representation of our knowledge of an underlying reality. Finally, Copenhagen-style interpretations claim that that there is no “reality” to be talked about at all. Bounding this menagerie of interpretations are several important theorems that restrict the options available. Bell’s theorem is the most famous (and most misunderstood) of these, but it is not the only one. In this talk, I will briefly lay out the measurement problem and its history, go over several of the theorems that constrain the possible solutions, and discuss a few of the families of quantum interpretations and the open problems that remain for each of them.
Slides here

Yuri Gershtein (Rutgers U.) "CMS Tracker for HL-LHC: an Exciting New Tool for Discovery"
2018-07-10 16:00 - 17:00
Abstract
The radiation environment at the High Luminosity LHC requires CMS to
replace its silicon tracker with one that is more radiation hard and granular.
The new tracker is designed twenty years after the original one, and has new unique
capabilities. It spans 8 units in rapidity, is more then twice lighter, and is capable to
participate in the first level of trigger decisions. In this talk, after sketching the
HL-LHC physics case, I will describe the detector design, FPGA-based track reconstruction,
and focus on one of many possible new opportunities it provides for new physics searches.

Laura Newburgh (Yale U.) "New Probes of Old Structure: Cosmology with 21cm Intensity Mapping and the Cosmic Microwave Background"
2018-07-19 16:00 - 17:00 | HYBRID 50A-5132 (Sessler Conference Room), https://lbnl.zoom.us/j/91782268585, 50A-5132
ABSTRACT:
Current cosmological measurements have left us with deep questions about our Universe: What caused the expansion of the Universe at the earliest times? How did structure form? What is Dark Energy and does it evolve with time? New experiments like CHIME, HIRAX, and ACTPol are poised to address these questions through 3-dimensional maps of structure and measurements of the polarized Cosmic Microwave Background. In this talk, I will describe how we will use 21cm intensity measurements from CHIME and HIRAX to place sensitive constraints on Dark Energy between redshifts 0.8 — 2.5, a poorly probed era corresponding to when Dark Energy began to impact the expansion history of the Universe. I will also discuss how we will use data from new instruments on the ACT telescope to constrain cosmological parameters like the total neutrino mass and probe structure at late times.
Slides Here

Sinead Farrington (U. Warwick) "Physics with Taus"
2018-09-06 16:00 - 17:00 | HYBRID 50A-5132 (Sessler Conference Room), https://lbnl.zoom.us/j/91782268585, 50A-5132
Abstract:
The identification of hadronically decaying tau leptons at the LHC is challenging. I will review the methods for tau reconstruction at ATLAS and how the identification of tau leptons has enabled several interesting and novel measurements in exotics and Higgs physics at the LHC. I will also look to the future and give some thoughts on next implementations for tau leptons at the LHC.

Martin White (UCB) "The cosmological legacy of Planck "
2018-09-20 16:00 - 17:00 | HYBRID 50A-5132 (Sessler Conference Room), https://lbnl.zoom.us/j/91782268585, 50A-5132
ABSTRACT:
The anisotropies in the cosmic microwave background radiation have become our most important cosmological fossil. The study of these “echoes of gravity” has revolutionized cosmology, stringently tested our models and allowed precise measurement of a host of important cosmological parameters. I will discuss how far we’ve come since the early detections of CMB anisotropies and in particular the cosmological legacy of the Planck mission.

Matt Pyle (UCB) "Athermal Phonon Detectors: World Leading Light Mass Dark Matter Sensitivity From Athermal Phonon Detectors + Preliminary Performance from Large Area Photon Detector for Next Generation Neutrinoless Double Beta Decay Experiments"
2018-09-27 16:00 - 17:00 | HYBRID 50A-5132 (Sessler Conference Room), https://lbnl.zoom.us/j/91782268585, 50A-5132
Abstract:

In this talk, we present the new world leading results from the first search of the SuperCDMS collaboration for inelastic electronic recoils from low mass dark matter dark matter (500keV – 100MeV) using our new single ionization sensitive cryogenic calorimeters.

We’ll also present preliminary performance of a large area cryogenic photon detector with applications in light mass dark matter and neutrinoless double beta decay. With 3eV sensitivity and 20us pulse rise time, it well surpasses all technical requirements for next generation cryogenic neutrinoless double beta decay experiments.

Kyle Helson (NASA Goddard) "The Status and Outlook of Cosmic Microwave Background Polarization Measurements"
2018-10-04 16:00 - 17:00 | HYBRID 50A-5132 (Sessler Conference Room), https://lbnl.zoom.us/j/91782268585, 50A-5132
Abstract:
The detailed characterization of the intensity and polarization Cosmic Microwave Background (CMB) radiation provides a powerful tool to constrain the properties of early Universe. The polarization induced by a stochastic gravitational wave background in this epoch induces a distinctive and measurable signature of primordial inflationary processes. Presently the field has a healthy contingent of ground, balloon, and space based missions. In this talk I will discuss a brief history of CMB measurements, the current status of the field and outlook for the future. I will also discuss on-going work at NASA Goddard Space Flight Center on the development of polarization-sensitive detectors for a future satellite CMB polarization mission and their application in ground based instruments.

Qian Xin (BNL) "Development of LArTPC for Neutrino Physics"
2018-10-11 16:00 - 17:00 | HYBRID 50A-5132 (Sessler Conference Room), https://lbnl.zoom.us/j/91782268585, 50A-5132
Abstract:
Liquid Argon Time Projection Chamber (LArTPC), with its mm-scale position resolution and the full-active-volume imaging-aided calorimetry, is an excellent device to detect accelerator neutrinos at GeV energy range. This technology may hold the key to search for new CP violation in the lepton sector, to determine the neutrino mass hierarchy, to precisely measure neutrino mixing parameters, to search for baryon number violation, and to search for sterile neutrino(s). In this talk, I will review the current status of the detector development. In particular, the challenges in TPC signal processing and event reconstruction will be discussed among other subjects.

Ning Bao (UCB/LBNL) "Quantum Information and Quantum Gravity"
2018-10-18 16:00 - 17:00 | HYBRID 50A-5132 (Sessler Conference Room), https://lbnl.zoom.us/j/91782268585, 50A-5132
ABSTRACT:
There has been much recent interest at the intersection of the fields of Quantum Information and Quantum Gravity. In this talk, I will go over some of the motivating principles/important work that has been done in this area, and explain some current research promising research trends.

Matthias Neubert (U. Mainz) "Effective Field Theory after a New-Physics Discovery"
2018-10-23 16:00 - 17:00 | HYBRID 50A-5132 (Sessler Conference Room), https://lbnl.zoom.us/j/91782268585, 50A-5132
ABSTRACT:

When a new heavy particle is discovered at the LHC, it will be interesting to study its decays into Standard Model particles using an effective field-theory framework. We point out that the proper effective theory must be based on non-local operators defined in soft-collinear effective theory (SCET). For the interesting case where the new resonance is a gauge-singlet spin-0 boson, which is the first member of a new sector governed by a mass scale M, we show how a consistent scale separation between M and the electroweak scale v is achieved up to next-to-next-to-leading order in lambda~v/M. The Wilson coefficients in the effective Lagrangian depend in a non-trivial way on the mass of the new resonance and the masses of yet undiscovered heavy particles. Large logarithms of the ratio M/v can be systematically resummed using the renormalization group. We develop a SCET toolbox, with which it is straightforward to construct the relevant effective Lagrangians for new heavy particles with other charges and spin.

Laura Newburgh (Yale U.) " Forefronts of Cosmology: Beyond Standard Model Physics with Upcoming CMB Instruments"
2018-10-25 16:00 - 17:00 | HYBRID 50A-5132 (Sessler Conference Room), https://lbnl.zoom.us/j/91782268585, 50A-5132
Abstracts
Upcoming new instruments to measure the polarized CMB promise to provide discriminatory limits on inflation, the number of light relic particles, and the sum of the neutrino masses, ushering in a new era of using the CMB as a probe of particle physics. Achieving these science goals requires highly sensitive instruments that are composed of enormous arrays of low noise detectors. In addition, systematic errors and foreground removal must be improved to lower the systematics floor below the statistical errors, necessitating dramatic improvements in calibration precision. In this talk, I will describe Simons Observatory (coming online in ~2021) and CMB-S4 (coming online in ~2027), their science goals, and how the twin requirements for sensitivity and systematics require a new approach to software for readout, data acquisition, and control systems. I will also discuss future directions for cosmology, including work in 21cm instruments to improve our understanding of the nature of Dark Energy.

Caterina Vernieri (Stanford) "Higgs to Beauty Quarks: First Observation of the Big Missing Piece"
2018-10-30 16:00 - 17:00 | HYBRID 50A-5132 (Sessler Conference Room), https://lbnl.zoom.us/j/91782268585, 50A-5132
ABSTRACT:
The Higgs boson discovery at the LHC marked a historic milestone in the study of fundamental particles and their interactions. Over the last six years, we have begun measuring its properties, which are essential to build a deep understanding of the Higgs sector of the Standard Model and to potentially uncover new phenomena. The Higgs’ favored decay mode to beauty (b) quarks (~60%) had so far remained elusive because of the overwhelming background of b-quark production due to strong interactions. Observing the Higgs decay to b-quarks was one of the critical missing pieces of our knowledge of the Higgs sector. Measuring this decay is a fundamental step to confirm the mass generation for fermions and may also provide hints of physics beyond the Standard Model. The CMS observation of the decay of the SM Higgs boson into a pair of b-quarks exploiting an exclusive production mode (VH) is yet another major milestone. This experimental achievement at the LHC, considered nearly impossible in the past, makes use of several advanced machine learning techniques to identify the b-quark distinctive signature, improve the Higgs boson mass resolution, and discriminate the Higgs boson signal from background processes.

Vivian Poulin (JHU) "Shedding Light on Dark Matter with the CMB: Implications for EDGES 21cm Signal"
2018-11-01 16:00 - 17:00 | HYBRID 50A-5132 (Sessler Conference Room), https://lbnl.zoom.us/j/91782268585, 50A-5132
ABSTRACT:
In this talk, I would like to review how the Cosmic Microwave Background (in particular its temperature and polarization anisotropies) can be used to perform both direct and indirect detection of Dark Matter. In a first part, I will show how the CMB can be used to put stringent constraints on DM models leading to energy injection, such as DM annihilations and decay or Primordial Black Holes matter accretion. I will compare CMB bounds to those coming from galactic cosmic and gamma ray searches and illustrate how the 21cm signal, a major target of next generation surveys, can be used to significantly improve over current limits. In a second part, I will discuss a recent puzzling absorption feature in the global 21cm signal observed by the EDGES experiment. Such feature could be explained by efficient scattering between DM and baryons in the late universe. I will show how the CMB strongly challenges such explanation of that signal.

Guy Ron (Jerusalem) "The Proton Radius - Old Measurements and New Ideas"
2018-11-06 16:00 - 17:00 | HYBRID 50A-5132 (Sessler Conference Room), https://lbnl.zoom.us/j/91782268585, 50A-5132
ABSTRACT:
The radius of the proton, generally assumed to be a well measured and understood quantity has recently come under scrutiny due to highly precise, yet conﬂicting, experimental results. These new results have generated a host of interpretations, none of which are completely satisfactory.
I will discuss the existing results, focusing on the discrepancy between the various extractions. I will brieﬂy discuss some theoretical attempts at reso-lution and focus on new scattering measurements, both planned and already underway, that are attempting to resolve the puzzle

Lucie Tvrznikova (Yale) "Sub-GeV dark matter searches and electric field studies for the LUX and LZ experiments "
2018-11-08 16:00 - 17:00 | HYBRID 50A-5132 (Sessler Conference Room), https://lbnl.zoom.us/j/91782268585, 50A-5132
ABSTRACT:
The Large Underground Xenon (LUX) and the LUX-ZEPLIN (LZ) detectors were designed to directly observe the interaction of dark matter (DM) with xenon target nuclei and thus probe much of the unexplored DM parameter space. I will discuss two novel direct detection methods, Bremsstrahlung and the Migdal effect, that were used by LUX to place limits on DM with masses of 0.4-5 GeV. I will also describe the development of a fully 3D model of electric fields that varied during the detector’s final 332 live-days of data acquisition. Since direct measurement of electric fields was not possible, this work enabled a thorough understanding of the detector throughout its operation. Lastly, I will present new results from the Xenon Breakdown Apparatus (XeBrA) built at LBNL to characterize the dielectric breakdown under high voltage in liquid xenon and liquid argon. Results from XeBrA will inform LZ and the future of noble liquid detector engineering.

Christian Herwig (U. Pennsylvania) " Targeting natural supersymmetry with top quarks"
2018-11-13 16:00 - 17:00 | HYBRID 50A-5132 (Sessler Conference Room), https://lbnl.zoom.us/j/91782268585, 50A-5132
Abstract:
What is the roadmap for the discovery of new physics in the
post-Higgs-observation era? The concept of naturalness can provide a
useful guiding principle, considering the interplay between new, heavy
physics and the electroweak scale. I will describe a new search for
natural models of supersymmetry from the ATLAS experiment via the
production of light top squarks. I will also discuss the impact of
precision top-quark measurements on future searches, highlighting a
recent measurement of quantum interference in top-quark production.

Stephane Brunet Cooperstein (Princeton) "Observation of Higgs Boson Decay to Bottom Quarks by the CMS Experiment"
2018-11-15 16:00 - 17:00 | HYBRID 50A-5132 (Sessler Conference Room), https://lbnl.zoom.us/j/91782268585, 50A-5132
ABSTRACT:
Since the discovery of the Higgs boson six years ago, great progress has been made in measuring precisely its properties. These measurements have primarily been made via rare Higgs boson decays to two photons or two Z bosons due to their distinct experimental signatures. Although 60% of the Higgs bosons are predicted to decay to bottom quarks, it was not originally expected to observe this Higgs boson dominant decay mode until much later in the LHC program due to an overwhelming background of bottom quarks produced via strong interactions. This milestone observation was achieved this summer by both the ATLAS and CMS experiments at the LHC. This seminar presents the observation of the Higgs boson decay to bottom quarks by the CMS experiment, with an emphasis on the latest results using data collected in 2017. The observation was made possible by incorporating deep learning techniques and novel analysis methods. This constitutes the first observation of a Yukawa coupling to down-type quarks. Moreover, it demonstrates the feasibility of the first precision measurements of Higgs bosons in the VH production mode in the near future.

Jesse Liu (U. Oxford) "Opening New Frontiers for Supersymmetry and Dark Matter at the LHC"
2018-11-20 16:00 - 17:00 | HYBRID 50A-5132 (Sessler Conference Room), https://lbnl.zoom.us/j/91782268585, 50A-5132
ABSTRACT:
Smoking gun signals for new physics at the LHC elude us.
What gaps remain under the lamppost? Where do we focus the next
generation of searches? This talk tackles these pressing problems by
highlighting new frontiers opened by recent theoretical surveys,
extending ATLAS beyond its design capability, and state-of-the-art
analysis strategies. Sensitivity to key supersymmetry targets
motivated by naturalness and WIMP dark matter are just surpassing two
decade old LEP limits. Striking blind spots remain around 100 GeV mass
scales that invite creative discovery strategies for future efforts.

Elodie Deborah Resseguie (U. Pennsylvania) "Electroweak SUSY Searches on ATLAS"
2018-11-27 16:00 - 17:00 | HYBRID 50A-5132 (Sessler Conference Room), https://lbnl.zoom.us/j/91782268585, 50A-5132
ABSTRACT:
Supersymmetry (SUSY) gives a solution to the naturalness problem of the Standard Model (SM) while providing a candidate for dark matter, solving two mysteries in modern physics. As the LHC collects more data and sets strong constraints on SUSY in the strong force sector within reach of the collider, new SUSY particles produced by electroweak (EWK) processes remain significantly less unconstrained. The EWK production of SUSY particles can be observed by their decay via the W and Z gauge bosons to final states with two or three leptons and missing transverse momentum from invisible particles. Two SUSY models are considered: one with a Wino next-to-lightest SUSY particle (NLSP) and Bino LSP, motivated by dark matter, and another with a Higgsino LSP, motivated by naturalness. The Higgsino LSP models are particularly challenging due to the small mass, or “compressed”, splittings, leading to low energy W and Z bosons. This requires specialized techniques for triggering, optimizing, and estimating backgrounds. I will present the latest ATLAS searches for both models, including the first result for Higgsino production since LEP, as well the outlook for future studies.

Karri DiPetrillo (Harvard U.) "Searching for long-lived particles with displaced vertices in ATLAS "
2018-11-29 16:00 - 17:00 | HYBRID 50A-5132 (Sessler Conference Room), https://lbnl.zoom.us/j/91782268585, 50A-5132
ABSTRACT:
Most searches for new physics at the Large Hadron Collider assume that a new particle produced in pp-collisions decays almost immediately, or is non-interacting and escapes the detector. However, a variety of new physics models predict particles which decay inside the detector at a discernible distance from the interaction point. Such long-lived particles would create spectacular signatures and evade many prompt searches. In this talk I will focus on a search for long-lived particles in events with a displaced vertex and a muon. I will also discuss challenges for the Muon Spectrometer in the face of increasing LHC luminosity.

Danielle Norcini (Yale) "PROSPECTing for reactor neutrinos at short baselines"
2018-12-04 16:00 - 17:00 | HYBRID 50A-5132 (Sessler Conference Room), https://lbnl.zoom.us/j/91782268585, 50A-5132
ABSTRACT:
Experiments at nuclear reactors have played a key role in determining the properties of the weakly-interacting neutrinos. PROSPECT is a next-generation experiment studying reactor neutrinos at very short baselines (< 10m) in an environment with limited shielding from cosmogenic backgrounds. Commissioned in March 2018, the compact, segmented detector unambiguously observed neutrinos in its first 2 hours of operation. In the months following, PROSPECT has performed a world-leading search for “sterile” neutrino oscillations and made the world-leading measurement of the uranium-235 antineutrino energy spectrum. This talk will detail the detector design, construction, and first physics results.

Scott Haselschwardt (UCSB) " Expected Performance of the LZ Outer Detector and a Radioassay of its Gadolinium-Loaded Liquid Scintillator"
2018-12-11 16:00 - 17:00 | HYBRID 50A-5132 (Sessler Conference Room), https://lbnl.zoom.us/j/91782268585, 50A-5132
ABSTRACT:
The LZ (LUX-ZEPLIN) experiment is a second generation direct dark matter detector under construction at the Sanford Underground Research Facility (SURF) in Lead, South Dakota, USA. LZ will use a 7 tonne central liquid xenon target, arranged in a dual-phase time projection chamber (TPC), to seek evidence for nuclear recoils from a hypothesized galactic flux of weakly interacting massive particles (WIMPs). Surrounding the LZ TPC will be an outer detector (OD) consisting of 17.3 tonnes of LAB-based gadolinium-loaded liquid scintillator (GdLS). The OD’s primary functions will be to tag neutron single-scatter events in the liquid xenon which could mimic a WIMP dark matter signal and to characterize the radiation environment of LZ. In this talk, I summarize the expected performance of the OD and report on the design and results of the “Screener”, a small liquid scintillator detector consisting of ≈ 23 kg of the GdLS to be used in the OD. The Screener was operated in the ultra-low-background environment of the former LUX water shield in the Davis Laboratory at SURF for radioassay of the GdLS. Careful selection of detector materials and use of ultra-low-background PMTs allows the measurement of a variety of radioimpurities. In particular, the 14C/12C ratio in the scintillator is measured, while the use of pulse shape discrimination allows the concentration of isotopes throughout the 238U, 235U, and 232Th chains to be measured by fitting the collected spectra from α and β events. The GdLS is found to meet the requirements for LZ, however, more aggressive purification is being implemented for the final GdLS product that ensures the OD will successfully carry out its role in the hunt for WIMP dark matter.

Brooke Russell (Yale) "Leveraging LArTPC Technology to Definitively Resolve the MiniBooNE Anomaly - An Elctron Neutrino Appearance Search at MicroBooNE"
2018-12-13 16:00 - 17:00 | HYBRID 50A-5132 (Sessler Conference Room), https://lbnl.zoom.us/j/91782268585, 50A-5132
ABSTRACT:
MicroBooNE is a single-phase liquid argon time projection chamber (LArTPC) short-baseline accelerator neutrino experiment located at Fermilab on the Booster neutrino beamline. MicroBooNE’s foremost scientific objective is to address the low energy excess of single shower electromagnetic events seen by the precursor MiniBooNE experiment. Leveraging the fine-grained drifted ionization charge signal from particle interactions, LArTPCs provide detailed topological and calorimetric information for physics analyses. By capitalizing on the interplay between scintillation light and 3D ionization charge imaging, a high efficiency, low background analysis is in development to address MiniBooNE’s anomalous result. The status of this analysis is described.

Sunny Vagnozzi (Stockholm University) "Recent Developments in Neutrino Cosmology"
2018-12-20 16:00 - 17:00 | INPA Common Room (50-5026), 50-5026
ABSTRACT:
A robust detection of neutrino masses is avowedly among the key goals of several upcoming Cosmic Microwave Background (CMB) and Large-Scale Structure (LSS) surveys. In this talk, I will describe recent progress in neutrino cosmology on three fronts. Firstly, I will illustrate the wealth of information on the sum of the neutrino masses obtainable from current cosmological probes, focusing on LSS data. Current upper limits begin favoring the normal neutrino mass ordering, emphasizing the need to develop statistical tools for quantifying this preference. Next, I will discuss galaxy bias as a limitation towards fully capitalizing on neutrino information hidden in LSS data, proposing a method for calibrating the scale-dependent galaxy bias using CMB lensing-galaxy cross-correlations. Moreover, in massive neutrino cosmologies the bias as usually defined is scale-dependent even on large scales: neglecting this effect will lead to incorrectly inferred parameters. Finally, I will take on a different angle and discuss degeneracies between neutrinos and other cosmological parameters. I will show how in certain physically motivated dynamical dark energy models the neutrino mass upper limits tighten instead of broadening, discussing implications for future laboratory determinations of the mass ordering. I will also discuss how neutrino unknowns affect constraints on inflationary models.

Dmitry Budker (UCB/Mainz) "Recent Results in Mains on the Search for Ultralight DM or Parity Violation in a Chain of Yb Isotopes, and Related Developments"
2019-01-03 16:00 - 17:00 | HYBRID 50A-5132 (Sessler Conference Room), https://lbnl.zoom.us/j/91782268585, 50A-5132

Stefano Soleti (Oxford/Harvard U.) "Searching for a Low-Energy Excess at MicroBOONE"
2019-01-08 16:00 - 17:00 | INPA Common Room (50-5026), 50-5026
ABSTRACT:
The last twenty years have seen a spectacular improvement in our understanding of neutrino oscillations and neutrino physics in general. However, several experiments have shown some puzzling results which do not fit the standard three-flavor mixing scheme of neutrinos. In particular, the LSND and MiniBooNE experiments observed an excess of low-energy electron neutrinos, which could be interpreted as the signature of a fourth, non-weakly interacting, neutrino. The goal of the MicroBooNE experiment, a liquid argon time projection chamber currently running at Fermilab, is to assess the nature of this excess. In this talk the first automated electron neutrino search in a LArTPC will be presented. This result is the first step towards a measurement of the low-energy excess at MicroBooNE.
