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All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

How silicon and boron dopants govern the cryogenic scintillation properties of N -type GaAs

This work is the first report describing how the concentrations of silicon and boron govern the cryogenic scintillation properties of n-type GaAs. It shows that valence band holes are promptly trapped on radiative centers and then combine radiatively with silicon donor band electrons at rates that increase with the density of free carriers. It also presents the range of silicon and boron concentrations needed for efficient light emission under X-ray excitation, which along with its low band gap and apparent absence of afterglow, make scintillating GaAs suitable for the detection of rare, low-energy electronic excitations from interacting dark matter particles. A total of 29 samples from four different suppliers were studied. Luminosities and timing responses were measured for the four principal emission bands centered at 860, 930, 1070, and 1335 nm, and for the total emissions. Excitation pulses of 40 kVp X-rays were provided by a light-excited X-ray tube driven by an ultra-fast laser. Scintillation emissions from 800 to 1350 nm were measured using an InGaAs photomultiplier. Within the concentration ranges of free carriers from 2 x 10 16 /cm 3 to 6 x 10 17 /cm 3 and boron from 1.5 × 10 18 /cm 3 to 6 x 10 18 /cm 3 , nine samples have luminosities > 70 photons/keV and two have luminosities > 110 photons/keV. Other samples in that range have lower luminosities due to higher concentrations of non-radiative centers. The decay times decrease by typically a factor of ten with increasing free carrier concentrations from 10 17 /cm 3 to 2 x 10 18 /cm 3 .

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2021

Cosmic antihelium-3 nuclei sensitivity of the GAPS experiment

The General Antiparticle Spectrometer (GAPS) is an Antarctic balloon experiment designed for low-energy (0.1-0.3 GeV/n) cosmic antinuclei as signatures of dark matter annihilation or decay. GAPS is optimized to detect low-energy antideuterons, as well as to provide unprecedented sensitivity to low-energy antiprotons and antihelium nuclei. The novel GAPS antiparticle detection technique, based on the formation, decay, and annihilation of exotic atoms, provides greater identification power for these low-energy antinuclei than previous magnetic spectrometer experiments. This work reports the sensitivity of GAPS to detect antihelium-3 nuclei, based on full instrument simulation, event reconstruction, and realistic atmospheric influence simulations. The report of antihelium nuclei candidate events by AMS-02 has generated considerable interest in antihelium nuclei as probes of dark matter and other beyond the Standard Model theories. GAPS is in a unique position to detect or set upper limits on the cosmic antihelium nuclei flux in an energy range that is essentially free of astrophysical background. In three 35-day long-duration balloon flights, GAPS will be sensitive to an antihelium flux on the level of $1.3^{+4.5}_{-1.2} $ ∙ 10 -6 m -2 sr -1 s -1 (GeV/n) -1 (95% confidence level) in the energy range of 0.11-0.3 GeV/n, opening a new window on rare cosmic physics.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2025

Extraction of the non-spin- and spin-transfer isovector responses via the 12 C ⁡( 10 Be, 10 B + 𝛾)⁢ 12 B reaction

The isovector response in 12 B was investigated via the 12 C ⁡( 10 Be, 10 B + 𝛾)⁢ 12 B* reaction at 100⁢𝐴MeV. By utilizing the 𝛾-decay properties of the 1.74 MeV 0 + and 0.718 MeV 1 + states in 10 B, the separate extraction of the non-spin-transfer (Δ⁢𝑆 = 0) and spin-transfer (Δ⁢𝑆 = 1) isovector responses up to an excitation energy of 50 MeV in 12 B in a single measurement is demonstrated. The experimental setup employed the S800 spectrometer to detect and analyze the 10 B ejectiles and the Gamma-Ray Energy Tracking In-beam Nuclear Array (GRETINA) for obtaining the Doppler-reconstructed spectrum for 𝛾 rays emitted in flight by 10 B. A 12 C foil was placed at the pivot point of the spectrograph. Here, the 12 B reaction product was not detected. Contributions from transitions associated with the transfer of different units of angular momentum in the non-spin- and spin-transfer responses were analyzed using a multipole decomposition analysis. The extracted non-spin-dipole (Δ⁢𝑆 = 0, Δ⁢𝐿 = 1) and spin-dipole (Δ⁢𝑆 = 1, Δ⁢𝐿 = 1) responses were found to be consistent with available data from other charge-exchange probes, validating the non-spin- and spin-transfer filters used. While statistical uncertainties and experimental resolutions were relatively large due to the modest intensity of the 10 Be secondary beam, the results show that, with the much higher intensities that will be available at new rare-isotope beam facilities, the ( 10 Be, 10 B + 𝛾) reaction and its Δ⁢𝑇 𝑧 = −1 partner, the ( 10 C, 10 B + 𝛾) reaction, are powerful tools for elucidating the isovector non-spin- and spin-transfer responses in nuclei.

Charge-exchange reactions↗
DOE OSTI2021

Beyond the Standard Model physics prospects at the Deep Underground Neutrino Experiment

The Deep Underground Neutrino Experiment (DUNE) is an international project for neutrino physics and proton-decay searches, currently in the design and planning stages. Once built, DUNE will consist of two detectors exposed to the world's most intense neutrino beam. The near detector at Fermilab will record neutrino interactions near the beginning of the beam line. The other, much larger, detector, comprising four 10-kton liquid argon time projection chambers (LArTPCs), will be installed at a depth of 1.5 km at the Sanford Underground Research Facility in South Dakota, about 1,300 km away from the neutrino source. The unique combination of the high-intensity neutrino beam, DUNE's high-resolution near detector system, and massive LArTPC far detector enables a variety of probes of Beyond-the-Standard-Model (BSM) physics, from the discovery of new particles (sterile neutrinos or dark matter), to precision tests of beyond the three-flavor mixing paradigm, non-standard neutrino interactions (NSIs), heavy neutral leptons, and the detailed study of rare processes (e.g., neutrino trident production). This article reviews these physics topics and discusses the prospects for their discovery at the DUNE experiment.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2024

Spontaneous fission of the odd- Z isotope 255 Db

Experiments conducted at Lawrence Berkeley National Laboratory's 88-Inch Cyclotron Facility aimed to produce and study the decay of the previously unobserved isotope 255 Db. This isotope was produced in the 206 Pb( 51 V, 2⁢n) 255 Db reaction, separated from unreacted beam material and reaction by-products with the Berkeley Gas-filled Separator, and then implanted into a double-sided silicon-strip detector at the BGS focal plane. Decay properties of 255 Db were determined from the analysis of evaporation residue (EVR) fission and EVR-α–α correlations. The properties of this new isotope of dubnium differ dramatically from those of its neighboring Db isotopes. 255 Db was found to decay primarily by spontaneous fission (SF) with a small α-decay branch, where the average half-life of the observed decays was t 1/2 = 2.6$^{+0.4}_{– 0.3}$ ms. Theoretical calculations were performed using the Wentzel-Kramers-Brillouin approximation, with parameters calculated within a self-consistent microscopic approach, to see if these unique properties could be reproduced. A SF half-life estimate is obtained that closely matches the measured value, while simultaneously pointing out the sensitivities that need to be further constrained in future work.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2021

Electromagnetic power of lightning superbolts from Earth to space

Lightning superbolts are the most powerful and rare lightning events with intense optical emission, first identified from space. Superbolt events occurred in 2010-2018 could be localized by extracting the high energy tail of the lightning stroke signals measured by the very low frequency ground stations of the World-Wide Lightning Location Network. Here, we report electromagnetic observations of superbolts from space using Van Allen Probes satellite measurements, and ground measurements, and with two events measured both from ground and space. From burst-triggered measurements, we compute electric and magnetic power spectral density for very low frequency waves driven by superbolts, both on Earth and transmitted into space, demonstrating that superbolts transmit 10-1000 times more powerful very low frequency waves into space than typical strokes and revealing that their extreme nature is observed in space. We find several properties of superbolts that notably differ from most lightning flashes; a more symmetric first ground-wave peak due to a longer rise time, larger peak current, weaker decay of electromagnetic power density in space with distance, and a power mostly confined in the very low frequency range. Their signal is absent in space during day times and is received with a long-time delay on the Van Allen Probes. These results have implications for our understanding of lightning and superbolts, for ionosphere-magnetosphere wave transmission, wave propagation in space, and remote sensing of extreme events.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2020

Attached Jet Velocity Profiles in Mixing Tanks

Free jets have been studied in detail over much of the last century, but the theory for offset and attached jets remains incomplete. Attached jets differ from free jets in that they lose momentum to nearby surfaces, attenuating their velocities. The velocity profiles of free circular jets are nearly Gaussian, with quantitative mathematical descriptions derived from first principles by Goertler and Tollmien (Rajaratnam, 1976). In contrast, mathematical descriptions of three-dimensional attached jets from circular nozzles remain much less mature. Agelin-Chaab and Tachie (2011) used particle imaging velocimetry of a three-dimensional attached jet to show that the scaled velocity decays with scaled distance from the nozzle with a power law exponent between -1.15 and -1.21, which is larger in magnitude than that of a free jet. However, quantitative analytical expressions for the velocity profiles of attached jets similar to those of free jets remain elusive. This paper addresses this critical gap. Here we evaluate the velocity profiles of three-dimensional offset jets emerging from circular nozzles that that become attached jets. These jets lose momentum due to interactions with nearby surfaces and are important to evaluating flows in mixing vessels and to suspending solids and trapped gases in radioactive waste tanks. Despite the importance of attached jets, prior insight has been purely experimental, limited to overly simplistic analytical models, or restricted to computationally expensive computational fluid dynamics case studies. We compare the expression of Verhoff (1963) to experimental results to find reasonable quantitative agreement. As stated by Agelin-Chaab and Tachie (2011), “detailed velocity measurements of 3D offset jets are rare.” Such remains the case. This study adds to the literature by providing information at two additional Reynolds numbers (1.43 106 and 1.87 106) and evaluating simple but accurate expressions for velocity profiles. These Reynolds numbers are an order of magnitude higher than prior reports. The semi-empirical stream wise velocity profile perpendicular to the surface proposed by Verhoff (1963) is in approximate agreement with these velocity profiles, which is surprising because these attached jets are three-dimensional instead of two-dimensional as evaluated by Verhoff. However, additional work is necessary to fully describe these profiles quantitatively.

jet, attached jet, offset jet↗
DOE OSTI2020

Measurement of the scintillation and ionization response of liquid xenon at MeV energies in the EXO-200 experiment

In this work, liquid xenon (LXe) is employed in a number of current and future detectors for rare event searches. We use the EXO-200 experimental data to measure the absolute scintillation and ionization yields generated by γ interactions from 228 Th (2615 keV), 226 Ra (1764 keV), and 60 Co (1332 keV and 1173 keV) calibration sources, over a range of electric fields. The W value that defines the recombination-independent energy scale is measured to be 11.5±0.5 (syst.) ±0.1 (stat.) eV. These data are also used to measure the recombination fluctuations in the number of electrons and photons produced by the calibration sources at the MeV scale, which deviate from extrapolations of lower-energy data. Additionally, a semiempirical model for the energy resolution of the detector is developed, which is used to constrain the recombination efficiency, i.e., the fraction of recombined electrons that result in the emission of a detectable photon. Detailed measurements of the absolute charge and light yields for MeV-scale electron recoils are important for predicting the performance of future neutrinoless double β -decay detectors.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2020

Shear Behavior of Artificial Clay Seams within Bedded Salt Structures

Bedded salt contains thin layers of clay, also known as clay seams, in-between far thicker layers of salt. These inhomogeneities are thought to have first-order effects on the closure of nearby drifts and potential roof collapses. Despite their importance, characterizations of the peak shear strength and residual shear strength of clay seams in salt are extremely rare in the published literature. A previous paper reported results from laboratory direct shear experiments on clay seam samples from the Permian Basin in New Mexico. These clay seams behaved similar to intact salt, which was attributed to the abundance of salt crystals intersecting the clay seams. None of those specimens contained a distinct ¼" - ½" (6 -12 mm) thick clay seam, as has been observed in drifts at the Waste Isolation Pilot Plant (WIPP). Due to the difficulty in obtaining WIPP samples with these types of clay seams, artificial seams of bentonite and brine sandwiched between sections of salt were created and shear tested. Eight 4" diameter samples were created with either a ¼" or ½" a thick seam and then consolidated at 3000 psi prior to shear testing. The direct shear tests on these samples were performed at nominal normal stresses representative of expected WIPP in-situ conditions (500 to 1500 psi). The resulting shear stress vs. shear displacement curves exhibited a peak followed by a gradual decay of shear strength. The shear stress never transitioned to a true residual shear stress plateau, so the final shear strength at the end of each test (0.75" of shear displacement) was analyzed instead. Both the peak shear strength and the final shear strength conformed to Mohr- Coulomb behavior with friction angles and cohesion strengths consistent with a saturated, highly consolidated, clay. These new artificial clay seam results and the previous clay-interspersed-with-salt results likely bound the expected shear behavior of WIPP clay seams.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
NASA NTRS2016

Review of the Theoretical and Experimental Status of Dark Matter Identification with Cosmic-Ray Antideuterons

Recent years have seen increased theoretical and experimental effort towards the first-ever detection of cosmic-ray antideuterons, in particular as an indirect signature of dark matter annihilation or decay. In contrast to indirect dark matter searches using positrons, antiprotons, or gamma-rays, which suffer from relatively high and uncertain astrophysical backgrounds, searches with antideuterons benefit from very suppressed conventional backgrounds, offering a potential breakthrough in unexplored phase space for dark matter. This article is based on the first dedicated cosmic-ray antideuteron workshop, which was held at UCLA in June 2014. It reviews broad classes of dark matter candidates that result in detectable cosmic-ray antideuteron fluxes, as well as the status and prospects of current experimental searches. The coalescence model of antideuteron production and the influence of antideuteron measurements at particle colliders are discussed. This is followed by a review of the modeling of antideuteron propagation through the magnetic fields, plasma currents, and molecular material of our Galaxy, the solar system, the Earth's geomagnetic field, and the atmosphere. Finally, the three ongoing or planned experiments that are sensitive to cosmic-ray antideuterons, BESS, AMS-02, and GAPS, are detailed. As cosmic-ray antideuteron detection is a rare event search, multiple experiments with orthogonal techniques and backgrounds are essential. Therefore, the combination of AMS-02 and GAPS antideuteron searches is highly desirable. Many theoretical and experimental groups have contributed to these studies over the last decade, this review aims to provide the first coherent discussion of the relevant dark matter theories that antideuterons probe, the challenges to predictions and interpretations of antideuteron signals, and the experimental efforts toward cosmic antideuteron detection.

Antideuteron Cosmic ray Dark matter↗
DOE OSTI2022

νi 13/2 structures in 155 Sm and 159 Gd: Supporting evidence of a Z = 60 deformed subshell gap

Maximal ground-state deformation should occur when both proton and neutron Fermi surfaces are located at midshell. However, subshell gaps that stabilize large deformation can exist at proton or neutron values other than midshell. One such gap may occur at Z = 60 in the rare-earth region, as the energy of the first 2 + states in even-even nuclei are often lowest in an isotonic chain for neodymium (Z = 60) rather than the midshell isotopes of dysprosium (Z = 66). Further evidence of this deformed gap has now been observed by investigating the signature splitting systematics of the νi 13/2 bands found in the odd-N, rare-earth nuclei. Furthermore, these were aided by the present observation of the νi 13/2 band in 159 Gd and the confirmation of the same structure in 155 Sm via the transfer of a neutron from a 160 Gd beam to a 154 Sm target.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
NASA NTRSDate not supplied

Coordinated analyses of hydrated Kuiper Belt dust

We report on coordinated mineralogical, chemical, and isotopic analyses of hydrated carbon-rich interplanetary dust particles (IDPs). We focus on hydrated IDPs that contain high solar flare track densities consistent with an origin in outer Solar System bodies such as Edgeworth-Kuiper belt objects (EKBOs) [1]. We are searching for evidence of the heavy water reservoir predicted by self-shielding models [2]. The IDPs were embedded in sulfur and microtome thin sections were obtained for Fourier-transform infrared (FTIR), transmission electron microscopy (TEM), and nanoSIMS analyses. The IDPs were only partly microtomed and the remainder was extracted from the sulfur and pressed into In or Au for high precision O isotopic analyses. The hydrated IDPs in this study are compact low-porosity objects with a mineralogy dominated by fine-grained saponite and lesser serpentine, Fe-Ni sulfides, Mg-Fe carbonates, rare crystaline silicates, and abundant organic matter. The C in the IDPs is abundant (typically >4X CI) and occurs as isolated nanoglobules and finely disseminated within the phyllosilicate matrix of the IDPs. TEM analyses of the nanoglobules show O-rich, S-depleted rims with higher carbonyl functionality than their cores. FTIR spectra show strong aliphatic C-H stretches consistent with the presence of short-chain aliphatic hydrocarbons in these IDPs. The oxygen isotopic compositions measured in 6 IDPs all plot within error of the CCAM line [3]. For several of the IDPs we were able to obtain multiple analyses. The ∆^(17)O values range from -23‰ up to +3.4‰ with most analyses clustering above the terrestrial fractionation line. The O isotopic compositions and the high C contents of these IDPs are distinct from known hydrated carbonaceous chondrites. The track-rich hydrated IDPs record parent body aqueous alteration effects through interactions with 16O-poor H2O on a EKBO parent body. The aqueous alteration activity likely resulted from the heat generated by collisional processes among EKBOs given that these objects are believed to have accreted late after the decay of 26Al [4].

Lindsay P. Keller↗
DOE OSTI2020

Spin-trap isomers in deformed, odd-odd nuclei in the light rare-earth region near $N=98$

Masses of neutron-rich, odd-odd Pm, Eu, and Tb nuclei near N = 98 were measured using the Canadian Penning Trap mass spectrometer at the Californium Rare Isotope Breeder Upgrade (CARIBU) facility. High-resolution mass measurements yielded the discovery of spin-trap isomers at N = 97 in Tb 162 , and in the N = 99 isotones of Pm 160 and Tb 164 . Furthermore, no evidence of long-lived isomers were observed at N = 95 in Eu 158 , at N = 97 in Pm 158 , nor at N = 101 in Eu 164 and Tb 166 . Here, these experimental observations are compared to results from multiquasiparticle blocking calculations.

150 ≤ A ≤ 189↗
DOE OSTI2022

Investigation of octupole collectivity near the A = 72 shape-transitional point

Enhanced octupole collectivity is expected in the neutron-deficient Ge, Se and Kr isotopes with neutron number N ≈ 40 and has indeed been observed for 70,72 Ge. Shape coexistence and configuration mixing are, however, a notorious challenge for theoretical models trying to reliably predict octupole collectivity in this mass region, which is known to feature rapid shape changes with changing nucleon number and spin of the system. To further investigate the microscopic configurations causing the prolate-oblate-triaxial shape transition at A ≈ 72 and their influence on octupole collectivity, the rare isotopes 72 Se and 74,76 Kr were studied via inelastic proton scattering in inverse kinematics. While significantly enhanced octupole strength of ≈32 Weisskopf units (W.u.) was observed for 72 Se, only strengths of ≈15 W.u. were observed for 74,76 Kr. In combination with existing data, the new data clearly question a simple origin of enhanced octupole strengths around N = 40. Furthermore, the present work establishes two regions of distinct octupole strengths with a sudden strength increase around the A = 72 shape transitional point.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
NASA NTRS2020

Microstructural and Isotopic Constraints on WL Rim Formation

Coordinated microanalyses of Wark-Lovering (WL) rims are needed to best understand their origin and to decipher their subsequent evolution both in the nebular and parent body settings. Here we present the mineralogy, petrology, microstructures, O isotopic compositions, and Al-Mg systematics of a WL rim on a Type B CAI, ‘‘Big Guy”, from the reduced CV3 chondrite Vigarano [1]. Our SEM and TEM study reveals seven distinct mineral layers in the WL rim that include: (1) gehlenite with rare grossite, (2) hibonite, (3) spinel with minor hibonite and perovskite, (4) zoned melilite (Åk(sub ~0-10)), (5) anorthite, (6) zoned diopside grading outwards from Al,Ti-rich to Al,Tipoor, and (7) forsterite intergrown with diopside. We infer a two-stage history in which WL rim formation was initiated by flash melting and extensive evaporation of the original inclusion edge, followed by subsequent condensation under highly dynamic conditions. The outermost edge of the CAI mantle is mineralogically and texturally distinct compared to the underlying mantle that is composed of coarse, zoned melilite (Åk(sub ~10-60)) grains. The mantle edge contains finegrained gehlenite with hibonite and rare grossite that likely formed by rapid crystallization from a Ca,Al-rich melt produced during a flash vaporization event [2]. These gehlenite and hibonite layers are surrounded by successive layers of spinel, melilite, diopside, and forsterite, indicating their sequential gas-solid reactions onto hibonite. Anorthite occurs as a discontinuous layer that corrodes adjacent melilite and Al-diopside, and appears to have replaced them [3,4], probably even later than the forsterite layer formation. All the WL rim minerals analyzed using the JSC NanoSIMS 50L are 16O-rich (Δ17O ≈ −23‰), indicating their formation in an 16O-rich gas reservoir. Our data are in contrast with many CV CAIs that show heterogeneous Δ 17O values across their WL rims [5]. Our Al-Mg data obtained using the UCLA ims-1290 ion microprobe of the CAI interior and the WL rim define a well-correlated isochron with (26Al/27Al)(sub 0) = 4.94 × 10(exp −5), indicating their synchronous formation ≤5 × 10(exp 4) years after the canonical CAI value. In contrast, no 26Mg excesses are observed in the WL rim anorthite, which suggests its later formation or later isotopic resetting in an 16O-rich gas reservoir, after 26Al had decayed.

Han, J.↗
NASA NTRS2017

The Beryllium-10 Abundance in an Unusual Hibonite-Perovskite Refractory Inclusion from Allende: Implications for the Origin of Be-10

Beryllium-10 (decays to B-10, t1/2 = t(sub 1/2) = 1.3 Myr) 1.3 Myr) is a radionuclide that exclusively requires a is a radionuclide that exclusively requires a spallation origin. Therefore, one could obtain important insights into the irradiation environment in the solar nebula by understanding the distribution and abundance of this radionuclide in meteoritic inclusions. Most previous data are derived from B isotopic analysis of coarse-grained CV3 Ca-Al-rich Inclusions (CAIs) that have AL-26.Al-27 Al close to the canonical level of 5 x 10 (exp -5) and inferred Be-10/Be-9 ratios between 4 x 10(exp -4) and 1 x 10 (exp -2=3) [1-5]. Al-26-depleted FUN (Fractionaed and Unknown Nuclear anomalies) CAIs are less studied due to their rarity. FUN CAIs are thought to have formed prior to homogenization of Al-26/Al-27 Al and stable isotope anomalies (e.g., Ti-50) in the solar nebula, and thus represent one of the oldest Solar System solids [6]. So far, only three FUN CAIs (Axtell 2771, KT-1 and HAL) from CV3 chondrites have been measured for Be-10. They are characterized by variable Be-10/Be-9 ratios between (2.7−4.4) × 10(exp -4) [4,7]. Another group of rare, Al-26-free and and isotopically more anomalous inclusions, namely platy hibonite crystals (PLACs) from CM2 chondrites, have well-defined Be-10/Be-9 = (5.3 +/- 1.0) x 10 (exp -4) [9]. Al-26-free CAIs appear to have lower Be-1-/Be-9 than Al-26-bearing CAIs, although large analytical errors associated with some data would allow for an apparent overlap. It has been argued that the observed Be-10 variation resulted from the in-situ production of this radionuclide in CAIs (or their precursors) by irradiation, and the ratio difference simply reflects the fluctuation in projectile fluences [e.g., 9]. Another observation in support of this explanation comes from these CAIs' initial B-10/B-11 ratios, most of which are higher than the chondritic value 0.2478 [10]. This has been interpreted as a result of mixing between spallogenic B (B-10/B-11 = 0.4, co-produced with Be-10 in the irradiated solids) and a chondritic component [5,8]. Alternatively, given that all the inferred ratios, most of which are higher than chondritic value 0.2478 [10]. This has been interpreted as a result of mixing between spallogenic B (B-10/B-11 = 0.4, co-produced with Be-10 in the irradiated solics) and a chondritic component [5,8], Alternatively, given that all the inferred ratios in CAIs never fall below 3x10(exp -4), it has been proposed that the Solar System formed with baseline Be-10/Be-9 at this level, which originated from cosmic ray irradiation of the parental molecular cloud, and any value higher than this is a result of additional in-situ spallation [4,11]. Although not explicitly stated in this model, one would expect that inclusions that incorporated the background Be-10 abundance should form with the chondritic B isotopic ratio. However, the three FUN CAIs all have supra-chondritic B-10/B-11 indicative of the presence of a spallogenic component. To test whether some Be-10 did come into the solar nebula by inheritance,a better understanding of Be-10/Be-9 and initial B-10/B-11 in Al-26-free isotopically anomalous samples is needed. Here we present the result of Be10−B-10 system in an unsual hibonite-perovskite inclusion SHAL (son of HAL) from Allende.

Liu, M-C.↗
NASA NTRSDate not supplied

Anomalous and Ungrouped Carbonaceous Chondrites in the US Antarctic Meteorite Collection and their Potential Relevance to Ryugu and Bennu

With two different carbonaceous asteroid sample return missions in full swing, attention has focused on what connections can be made between the asteroid samples and the wide range of carbonaceous chondrite meteorites in worldwide collections. The US Antarctic meteorite collection contains nearly 1000 carbonaceous chondrites of various types including many in well-established groups as well as ungrouped, unusual or anomalous groups [1]. Some of the latter have been included in, or are possibly related to, recently proposed new carbonaceous chondrite classifications – CA and CY chondrites [2,3]. In addition to these, there are numerous ungrouped samples that have properties intermediate between established groups (like CM and CO; [4]), distinct from any other groups [5], or have anomalous properties that might be attributable to parent body processes such as heating, fluid interaction, or impacts [6]. Some CM anomalous or ungrouped chondrites share spectral features with Ryugu, which has a small hydration peak arguably due to hydrated minerals left after either impact heating or shock in carbonaceous chondrites [7]. PCA 91008, PCA 02012, GRO 95566, and LEW 85311 are all CMs that have experienced heating or metamorphism that may be due to impacts, solar radiation, or radiogenic decay [6]. These samples all have low H contents, C/H (bulk), and low 17O [6,8] and may hold clues to understanding the mineralogy of Ryugu, or interpretations of its spectral properties. WIS 91600, on the other hand, appears to be related to several other highly altered CM [6], and shares properties with the newly proposed CY chondrites [6]. An understanding of this grouplet will also aid in the interpretation of Bennu samples which have strong hydration features. In addition, ungrouped carbonaceous chondrites may provide valuable insights into the aqueous alteration potentially recorded in Bennu and Ryugu samples; such as the relatively moderate aqueous alteration recognized and dated at 4-5 myr after CAIs in MAC 88107 (C2-ungrouped) by [9] to the extensive aqueous alteration apparent in MIL 090292 (C1-ungrouped) [10]. Finally, LON 94101/94102 is a brecciated CM chondrite with numerous lithologies. Its appearance is similar to some of the brecciated lithologies visible at the surface of Bennu and Ryugu [11]. Although CM chondrites with multiple lithologies are common (e.g., [12]), the lithologies are often difficult to resolve at the hand specimen scale and only after some detailed e-beam characterization are the subtle lithologic differences evident (e.g., [13]). LON 94102 contains visibly distinct clasts at the hand specimen scale, relatively rare for CM breccias. The largest CM chondrites by mass from the U.S. Antarctic meteorite collection may provide insights into the extent of brecciation and heterogeneity within more typical CM chondrite-like source asteroids. For example, recent curation CT scans [14] show possible clasts within in a subsplit of ALH 83100 (CM1/2) which is the largest CM chondrite or CM chondrite pairing group in the U.S. Antarctic collection with an original mass of 3.019 kg. Similar work on additional subsplits or meteorites may aid our understanding of heterogeneity within CM chondrites from Antarctica. Initial classification of CM chondrites in U.S. Antarctic meteorite collection includes preliminary pairing when petrographically similar CM chondrites that have been previously found in the same field area. The two largest CM chondrite preliminary pairing groups by mass are the ALH 83102 (CM2) pairing group with an original mass of 2.554 kg and the EET 96005 (CM2) pairing group with an original mass of 1.125 kg. However, preliminary pairing groups assigned at classification—intrinsically— do not include stones that are petrographically distinct. Rigorous pairing group studies of CM chondrites from specific field sites are needed to investigate if there is unrecognized heterogeneity in CM chondrites from Antarctica that may represent common asteroid impactors (pre-atmospheric entry asteroids/meteoroids). Detailed pairing studies have the potential to recognize initial stones with multiple lithologies and investigate if there are stones that only sample one of those respective lithologies in the collection. These groups of heated CMs, extensively hydrated CMs, intermediate between CM and CO chondrites, and brecciated samples are all potentially relevant to Bennu and Ryugu samples, where heating, hydration, and brecciation have all come into play. These bodies might also be comprised of material intermediate to CM and CO chondrites, or at least distinct from the well-established CC groups. These small and unusual groups of carbonaceous chondrites may help to unlock new information about early solar system processes and aid in the understanding of the evolution of these carbonaceous asteroids.

meteorites↗
DOE OSTI2023

Quantum Information Science in High Energy Physics at the Large Hadron Collider (Final Report-QuantISED)

We pursue scientific research at the interface of High Energy Physics and Quantum Information Science. This includes studies of thermal radiation and quantum entanglement in high-energy collisions at the Large Hadron Collider (LHC), with special emphasis on entanglement entropy and the Higgs boson. This project has also been extended to include quantum entanglement and charged current weak interactions using Fermilab results. And most recently, we have begun tests of the temporal entanglement using LHC data. Collider experiments such as proton-proton collisions at the LHC yield hadrons that exhibit an exponential behavior at low transverse momenta. This surprising behavior is seen in data from both the ATLAS and CMS collaborations. We attribute this phenomenon to quantum entanglement between the regions in the nucleon wave function. The exponential component to the transverse momentum distribution is a result of thermal radiation that is akin to Hawking or Unruh radiation that should exist at the event horizon of astrophysical black holes and neutron stars. The Principal Investigator, in collaboration with a theoretical physicist at Stony Brook University and Brookhaven National Laboratory, and with Yale University students, has shown evidence for this thermal radiation in several production and decay processes in the ATLAS and CMS data, and its connection to entanglement entropy (O.K. Baker and D.E Kharzeev, Phys. Rev. D 98, 054007 (2018)), including even the Higgs boson sector. Interestingly, this thermal behavior is also seen in momentum distributions of charged current weak interactions according to our studies. These findings suggest a deep connection between quantum entanglement (entanglement entropy) and thermalization in both hadron collisions at the energy frontier and neutrino scattering at the intensity frontier. We have confirmed the proposed relation between the effective temperature and the hard-scattering scale at lower energies using the most recent LHC data for the following systems: Higgs bosons, top quarks, and charged hadrons. Additionally, we have results for hadron production in neutrino scattering from nuclei using Fermilab weak interaction data. This study is carried out using data from the MINERvA collaboration. In those cases where entanglement is expected, there is an exponential component to the momentum distribution, while this component is absent in those processes where no entanglement is expected. This research thus tests the hypothesis about a link between quantum entanglement and thermalization in strong and weak interactions. See Phys Lett B 811, 135948 (2020). We also initiated research applying a quantum search algorithm (Grover's Algorithm) to LHC data. This quantum algorithm was used to show how rare events in LHC data can be searched for in large, unsorted databases, with quadratic speedup compared to classical search algorithms on classical computers. See "Application of a Quantum Search Algorithm to High- Energy Physics Data at the Large Hadron Collider", arXiv:2010.00649 [quant-ph].

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗