Physics and Astronomy

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1D to 3D Crossover of a Spin-Imbalanced Fermi Gas
(American Physical Society, 2016) Revelle, Melissa C.; Fry, Jacob A.; Olsen, Ben A.; Hulet, Randall G.; Rice Center for Quantum Materials
We have characterized the one-dimensional (1D) to three-dimensional (3D) crossover of a two-component spin-imbalanced Fermi gas of 6Li atoms in a 2D optical lattice by varying the lattice tunneling and the interactions. The gas phase separates, and we detect the phase boundaries using in situ imaging of the inhomogeneous density profiles. The locations of the phases are inverted in 1D as compared to 3D, thus providing a clear signature of the crossover. By scaling the tunneling rate t with respect to the pair binding energy εB, we observe a collapse of the data to a universal crossover point at a scaled tunneling value of ˜tc=0.025(7).
222Rn emanation measurements for the XENON1T experiment
(Springer Nature, 2021) XENON Collaboration
The selection of low-radioactive construction materials is of utmost importance for the success of low-energy rare event search experiments. Besides radioactive contaminants in the bulk, the emanation of radioactive radon atoms from material surfaces attains increasing relevance in the effort to further reduce the background of such experiments. In this work, we present the 222Rn emanation measurements performed for the XENON1T dark matter experiment. Together with the bulk impurity screening campaign, the results enabled us to select the radio-purest construction materials, targeting a 222Rn activity concentration of 10μBq/kg in 3.2t of xenon. The knowledge of the distribution of the 222Rn sources allowed us to selectively eliminate problematic components in the course of the experiment. The predictions from the emanation measurements were compared to data of the 222Rn activity concentration in XENON1T. The final 222Rn activity concentration of (4.5±0.1)μBq/kg in the target of XENON1T is the lowest ever achieved in a xenon dark matter experiment.
A Detailed Clinical Case of Localized Prostate Tumors Treated with Nanoparticle-Assisted Sub-Ablative Laser Ablation
(MDPI, 2024) Kadria-Vili, Yara; Schwartz, Jon A.; Polascik, Thomas J.; Goodrich, Glenn P.; Jorden, David; Pinder, Diane; Halas, Naomi J.; Rastinehad, Ardeshir R.; Laboratory for Nanophotonics
AuroLase® Therapy—a nanoparticle-enabled focal therapy—has the potential to safely and effectively treat localized prostate cancer (PCa), preserving baseline functionality. This article presents a detailed case of localized PCa treated with AuroLase, providing insight on expectations from the diagnosis of PCa to one year post-treatment. AuroLase Therapy is a two-day treatment consisting of a systemic infusion of gold nanoshells (~150-nm hydrodynamic diameter) on Day 1, and sub-ablative laser treatment on Day 2. Multiparametric MRI (mpMRI) was used for tumor visualization, treatment planning, and therapy response assessment. The PCa was targeted with a MR/Ultrasound-fusion (MR/US) transperineal approach. Successful treatment was confirmed at 6 and 12 months post-treatment by the absence of disease in MR/US targeted biopsies. On the mpMRI, confined void space was evident, an indication of necrotic tissues encompassing the treated lesion, which was completely resolved at 12 months, forming a band-like scar with no evidence of recurrent tumor. The patient’s urinary and sexual functions were unchanged. During the one-year follow-up, changes on the DCE sequence and in the Ktrans and ADC values assist in qualitatively and quantitatively evaluating tissue changes. The results highlight the potential of gold-nanoparticle-enabled sub-ablative laser treatment to target and control localized PCa, maintain quality of life, and preserve baseline functionality.
A Dust-trapping Ring in the Planet-hosting Disk of Elias 2-24
(IOP Publishing, 2024) Carvalho, Adolfo S.; Pérez, Laura M.; Sierra, Anibal; Mellado, Maria Jesus; Hillenbrand, Lynne A.; Andrews, Sean; Benisty, Myriam; Birnstiel, Tilman; Carpenter, John M.; Guzmán, Viviana V.; Huang, Jane; Isella, Andrea; Kurtovic, Nicolas; Ricci, Luca; Wilner, David J.
Rings and gaps are among the most widely observed forms of substructure in protoplanetary disks. A gap–ring pair may be formed when a planet carves a gap in the disk, which produces a local pressure maximum following the gap that traps inwardly drifting dust grains and appears as a bright ring owing to the enhanced dust density. A dust-trapping ring would provide a promising environment for solid growth and possibly planetesimal production via the streaming instability. We present evidence of dust trapping in the bright ring of the planet-hosting disk Elias 2-24, from the analysis of 1.3 and 3 mm Atacama Large Millimeter/submillimeter Array observations at high spatial resolution (0.″029, 4.0 au). We leverage the high spatial resolution to demonstrate that larger grains are more efficiently trapped and place constraints on the local turbulence (8 × 10−4 < α turb < 0.03) and the gas-to-dust ratio (Σ g /Σ d < 30) in the ring. Using a scattering-included marginal probability analysis, we measure a total dust disk mass of . We also show that at the orbital radius of the proposed perturber the gap is cleared of material down to a flux contrast of 10−3 of the peak flux in the disk.
A general theoretical framework to design base editors with reduced bystander effects
(Springer Nature, 2021) Wang, Qian; Yang, Jie; Zhong, Zhicheng; Vanegas, Jeffrey A.; Gao, Xue; Kolomeisky, Anatoly B.; Center for Theoretical Biological Physics
Base editors (BEs) hold great potential for medical applications of gene therapy. However, high precision base editing requires BEs that can discriminate between the target base and multiple bystander bases within a narrow active window (4 – 10 nucleotides). Here, to assist in the design of these optimized editors, we propose a discrete-state stochastic approach to build an analytical model that explicitly evaluates the probabilities of editing the target base and bystanders. Combined with all-atom molecular dynamic simulations, our model reproduces the experimental data of A3A-BE3 and its variants for targeting the “TC” motif and bystander editing. Analyzing this approach, we propose several general principles that can guide the design of BEs with a reduced bystander effect. These principles are then applied to design a series of point mutations at T218 position of A3G-BEs to further reduce its bystander editing. We verify experimentally that the new mutations provide different levels of stringency on reducing the bystander editing at different genomic loci, which is consistent with our theoretical model. Thus, our study provides a computational-aided platform to assist in the scientifically-based design of BEs with reduced bystander effects.
A high-throughput three-dimensional cell migration assay for toxicity screening with mobile device-based macroscopic image analysis
(Nature Publishing Group, 2013) Timm, David M.; Chen, Jianbo; Sing, David; Gage, Jacob A.; Haisler, William L.; Neeley, Shane K.; Raphael, Robert M.; Dehghani, Mehdi; Rosenblatt, Kevin P.; Killian, T.C.; Tseng, Hubert; Souza, Glauco R.
There is a growing demand for in vitro assays for toxicity screening in three-dimensional (3D) environments. In this study, 3D cell culture using magnetic levitation was used to create an assay in which cells were patterned into 3D rings that close over time. The rate of closure was determined from time-lapse images taken with a mobile device and related to drug concentration. Rings of human embryonic kidney cells (HEK293) and tracheal smooth muscle cells (SMCs) were tested with ibuprofen and sodium dodecyl sulfate (SDS). Ring closure correlated with the viability and migration of cells in two dimensions (2D). Images taken using a mobile device were similar in analysis to images taken with a microscope. Ring closure may serve as a promising label-free and quantitative assay for high-throughput in vivo toxicity in 3D cultures.
A JWST Preview: Adaptive-optics Images of H2, Br-γ, and K-continuum in Carina's Western Wall
(IOP, 2020) Hartigan, Patrick; Downes, Turlough; Isella, Andrea
We present the first wide-field near-infrared adaptive-optics images of Carina's Western Wall (G287.38-0.62), one of the brightest and most well-defined irradiated interfaces known in a region of massive star formation. The new narrowband H2 2.12 μm, Br-γ and K-continuum images from Gemini South trace the photoevaporative flow from the cloud and identify locations where UV radiation from the surrounding massive stars excites molecular hydrogen to fluoresce. With a field of view of ~1farcm5 × 2farcm9 and spatial resolution between 60 and 110 mas, the new images show a spectacular level of detail over a large area, and presage what the James Webb Space Telescope (JWST) should achieve. The Wall is convex in shape, with a large triangular-shaped extension near its apex. The interface near the apex consists of 3–4 regularly spaced ridges with projected spacings of ~2000 au, suggestive of a large-scale dynamically important magnetic field. The northern edge of the Wall breaks into several swept-back fragments of width ~1800 au that resemble Kelvin–Helmholtz instabilities, and the southern part of the Wall also shows complex morphologies including a sinusoidal-like variation with a half-wavelength of 2500 au. Though the dissociation front must increase the density along the surface of the Wall, it does not resolve into pillars that point back to the ionization sources, as could occur if the front triggered new stars to form. We discovered that MHO 1630, an H2 outflow with no clear driving source in the northern portion of the Wall, consists of a series of bow shocks arrayed in a line.
A Lower Bound on Dark Matter Mass
(American Physical Society, 2024) Amin, Mustafa A.; Mirbabayi, Mehrdad
We argue that there is a lower bound of order 10−19 eV on dark matter mass if it is produced after inflation via a process with finite correlation length. We rely on nondetection of free-streaming suppression and white-noise enhancement of density perturbations as the observational inputs.
A magnesium-induced triplex pre-organizes the SAM-II riboswitch
(Public Library of Science, 2017) Roy, Susmita; Lammert, Heiko; Hayes, Ryan L.; Chen, Bin; LeBlanc, Regan; Dayie, T.Kwaku; Onuchic, José Nelson; Sanbonmatsu, Karissa Y.; Center for Theoretical Biological Physics
Our 13C- and 1H-chemical exchange saturation transfer (CEST) experiments previously revealed a dynamic exchange between partially closed and open conformations of the SAM-II riboswitch in the absence of ligand. Here, all-atom structure-based molecular simulations, with the electrostatic effects of Manning counter-ion condensation and explicit magnesium ions are employed to calculate the folding free energy landscape of the SAM-II riboswitch. We use this analysis to predict that magnesium ions remodel the landscape, shifting the equilibrium away from the extended, partially unfolded state towards a compact, pre-organized conformation that resembles the ligand-bound state. Our CEST and SAXS experiments, at different magnesium ion concentrations, quantitatively confirm our simulation results, demonstrating that magnesium ions induce collapse and pre-organization. Agreement between theory and experiment bolsters microscopic interpretation of our simulations, which shows that triplex formation between helix P2b and loop L1 is highly sensitive to magnesium and plays a key role in pre-organization. Pre-organization of the SAM-II riboswitch allows rapid detection of ligand with high selectivity, which is important for biological function.
A mechanism-based computational model to capture the interconnections among epithelial-mesenchymal transition, cancer stem cells and Notch-Jagged signaling
(Oncotarget, 2018) Bocci, Federico; Jolly, Mohit Kumar; George, Jason Thomas; Levine, Herbert; Onuchic, José Nelson; Center for Theoretical Biological Physics
Epithelial-mesenchymal transition (EMT) and cancer stem cell (CSCs) formation are two fundamental and well-studied processes contributing to cancer metastasis and tumor relapse. Cells can undergo a partial EMT to attain a hybrid epithelial/mesenchymal (E/M) phenotype or a complete EMT to attain a mesenchymal one. Similarly, cells can reversibly gain or lose 'stemness'. This plasticity in cell states is modulated by signaling pathways such as Notch. However, the interconnections among the cell states enabled by EMT, CSCs and Notch signaling remain elusive. Here, we devise a computational model to investigate the coupling among the core decision-making circuits for EMT, CSCs and Notch. Our model predicts that hybrid E/M cells are most likely to associate with stem-like traits and enhanced Notch-Jagged signaling – a pathway implicated in therapeutic resistance. Further, we show that the position of the 'stemness window' on the 'EMT axis' is varied by altering the coupling strength between EMT and CSC circuits, and/or modulating Notch signaling. Finally, we analyze the gene expression profile of CSCs from several cancer types and observe a heterogeneous distribution along the 'EMT axis', suggesting that different subsets of CSCs may exist with varying phenotypes along the epithelial-mesenchymal axis. We further investigate therapeutic perturbations such as treatment with metformin, a drug associated with decreased cancer incidence and increased lifespan of patients. Our mechanism-based model explains how metformin can both inhibit EMT and blunt the aggressive potential of CSCs simultaneously, by driving the cells out of a hybrid E/M stem-like state with enhanced Notch-Jagged signaling.
A Mott insulator continuously connected to iron pnictide superconductors
(Springer Nature, 2016) Song, Yu; Yamani, Zahra; Cao, Chongde; Li, Yu; Zhang, Chenglin; Chen, Justin S.; Huang, Qingzhen; Wu, Hui; Tao, Jing; Zhu, Yimei; Tian, Wei; Chi, Songxue; Cao, Huibo; Huang, Yao-Bo; Dantz, Marcus; Schmitt, Thorsten; Yu, Rong; Nevidomskyy, Andriy H.; Morosan, Emilia; Si, Qimiao; Dai, Pengcheng; Rice Center for Quantum Materials
Iron-based superconductivity develops near an antiferromagnetic order and out of a bad-metal normal state, which has been interpreted as originating from a proximate Mott transition. Whether an actual Mott insulator can be realized in the phase diagram of the iron pnictides remains an open question. Here we use transport, transmission electron microscopy, X-ray absorption spectroscopy, resonant inelastic X-ray scattering and neutron scattering to demonstrate that NaFe1−xCuxAs near x≈0.5 exhibits real space Fe and Cu ordering, and are antiferromagnetic insulators with the insulating behaviour persisting above the Néel temperature, indicative of a Mott insulator. On decreasing x from 0.5, the antiferromagnetic-ordered moment continuously decreases, yielding to superconductivity ∼x=0.05. Our discovery of a Mott-insulating state in NaFe1−xCuxAs thus makes it the only known Fe-based material, in which superconductivity can be smoothly connected to the Mott-insulating state, highlighting the important role of electron correlations in the high-Tc superconductivity.
A New High-Performance Gadonanotube-Polymer Hybrid Material for Stem Cell Labeling and Tracking by MRI
(Hindawi, 2018) Moghaddam, Sakineh E.; Hernández-Rivera, Mayra; Zaibaq, Nicholas G.; Ajala, Afis; Cabreira-Hansen, Maria da Graça; Mowlazadeh-Haghighi, Saghar; Willerson, James T.; Perin, Emerson C.; Muthupillai, Raja; Wilson, Lon J.
A gentle, rapid method has been developed to introduce a polyacrylic acid (PAA) polymer coating on the surface of gadonanotubes (GNTs) which significantly increases their dispersibility in water without the need of a surfactant. As a result, the polymer, with its many carboxylic acid groups, coats the surface of the GNTs to form a new GNT-polymer hybrid material (PAA-GNT) which can be highly dispersed in water (ca. 20 mg·mL−1) at physiological pH. When dispersed in water, the new PAA-GNT material is a powerful MRI contrast agent with an extremely short water proton spin-lattice relaxation time (T1) which results in a T1-weighted relaxivity of 150 mM−1·s−1 per Gd3+ ion at 1.5 T. Furthermore, the PAA-GNTs have been used to safely label porcine bone-marrow-derived mesenchymal stem cells for magnetic resonance imaging. The labeled cells display excellent image contrast in phantom imaging experiments, and transmission electron microscopy images of the labeled cells reveal the presence of highly dispersed PAA-GNTs within the cytoplasm with 1014 Gd3+ ions per cell.
A New Look at T Tauri Star Forbidden Lines: MHD-driven Winds from the Inner Disk
(IOP Publishing, 2018) Fang, Min; Pascucci, Ilaria; Edwards, Suzan; Gorti, Uma; Banzatti, Andrea; Flock, Mario; Hartigan, Patrick; Herczeg, Gregory J.; Dupree, Andrea K.
Magnetohydrodynamic (MHD) and photoevaporative winds are thought to play an important role in the evolution and dispersal of planet-forming disks. We report the first high-resolution (Δ v ∼ 6 km s −1 ) analysis of [S ii ] λ 4068, [O i ] λ 5577, and [O i ] λ 6300 lines from a sample of 48 T Tauri stars. Following Simon et al. we decompose them into three kinematic components: a high-velocity component (HVC) associated with jets, and low-velocity narrow (LVC-NC) and broad (LVC-BC) components. We confirm previous findings that many LVCs are blueshifted by more than 1.5 km s −1 and thus most likely trace a slow disk wind. We further show that the profiles of individual components are similar in the three lines. We find that most LVC-NC and LVC-BC line ratios are explained by thermally excited gas with temperatures between 5000 and 10,000 K and electron densities of ∼10 7 –10 8 cm −3 . The HVC ratios are better reproduced by shock models with a pre-shock H number density of ∼10 6 –10 7 cm −3 . Using these physical properties, we estimate ##IMG## [http://ej.iop.org/images/0004-637X/868/1/28/apjaae780ieqn1.gif] $\dotM_\mathrmwind/\dotM_\mathrmacc$ for the LVC and ##IMG## [http://ej.iop.org/images/0004-637X/868/1/28/apjaae780ieqn2.gif] $\dotM_\mathrmjet/\dotM_\mathrmacc$ for the HVC. In agreement with previous work, the mass carried out in jets is modest compared to the accretion rate. With the likely assumption that the LVC-NC wind height is larger than the LVC-BC, the LVC-BC ##IMG## [http://ej.iop.org/images/0004-637X/868/1/28/apjaae780ieqn3.gif] $\dotM_\mathrmwind/\dotM_\mathrmacc$ is found to be higher than the LVC-NC. These results suggest that most of the mass loss occurs close to the central star, within a few au, through an MHD-driven wind. Depending on the wind height, MHD winds might play a major role in the evolution of the disk mass.
A next-generation liquid xenon observatory for dark matter and neutrino physics
(IOP Publishing, 2022) Aalbers, J.; AbdusSalam, S.S.; Abe, K.; Aerne, V.; Agostini, F.; Maouloud, S. Ahmed; Akerib, D.S.; Akimov, D.Y.; Akshat, J.; Musalhi, A.K. Al; Alder, F.; Alsum, S.K.; Althueser, L.; Amarasinghe, C.S.; Amaro, F.D.; Ames, A.; Anderson, T.J.; Andrieu, B.; Angelides, N.; Angelino, E.; Angevaare, J.; Antochi, V.C.; Martin, D. Antón; Antunovic, B.; Aprile, E.; Araújo, H.M.; Armstrong, J.E.; Arneodo, F.; Arthurs, M.; Asadi, P.; Baek, S.; Bai, X.; Bajpai, D.; Baker, A.; Balajthy, J.; Balashov, S.; Balzer, M.; Bandyopadhyay, A.; Bang, J.; Barberio, E.; Bargemann, J.W.; Baudis, L.; Bauer, D.; Baur, D.; Baxter, A.; Baxter, A.L.; Bazyk, M.; Beattie, K.; Behrens, J.; Bell, N.F.; Bellagamba, L.; Beltrame, P.; Benabderrahmane, M.; Bernard, E.P.; Bertone, G.F.; Bhattacharjee, P.; Bhatti, A.; Biekert, A.; Biesiadzinski, T.P.; Binau, A.R.; Biondi, R.; Biondi, Y.; Birch, H.J.; Bishara, F.; Bismark, A.; Blanco, C.; Blockinger, G.M.; Bodnia, E.; Boehm, C.; Bolozdynya, A.I.; Bolton, P.D.; Bottaro, S.; Bourgeois, C.; Boxer, B.; Brás, P.; Breskin, A.; Breur, P. A.; Brew, C.A.J.; Brod, J.; Brookes, E.; Brown, A.; Brown, E.; Bruenner, S.; Bruno, G.; Budnik, R.; Bui, T.K.; Burdin, S.; Buse, S.; Busenitz, J.K.; Buttazzo, D.; Buuck, M.; Buzulutskov, A.; Cabrita, R.; Cai, C.; Cai, D.; Capelli, C.; Cardoso, J.M.R.; Carmona-Benitez, M.C.; Cascella, M.; Catena, R.; Chakraborty, S.; Chan, C.; Chang, S.; Chauvin, A.; Chawla, A.; Chen, H.; Chepel, V.; Chott, N.I.; Cichon, D.; Chavez, A. Cimental; Cimmino, B.; Clark, M.; Co, R.T.; Colijn, A.P.; Conrad, J.; Converse, M.V.; Costa, M.; Cottle, A.; Cox, G.; Creaner, O.; Garcia, J.J. Cuenca; Cussonneau, J.P.; Cutter, J.E.; Dahl, C.E.; D’Andrea, V.; David, A.; Decowski, M.P.; Dent, J.B.; Deppisch, F.F.; Viveiros, L. de; Gangi, P. Di; Giovanni, A. Di; Pede, S. Di; Dierle, J.; Diglio, S.; Dobson, J.E.Y.; Doerenkamp, M.; Douillet, D.; Drexlin, G.; Druszkiewicz, E.; Dunsky, D.; Eitel, K.; Elykov, A.; Emken, T.; Engel, R.; Eriksen, S.R.; Fairbairn, M.; Fan, A.; Fan, J.J.; Farrell, S.J.; Fayer, S.; Fearon, N.M.; Ferella, A.; Ferrari, C.; Fieguth, A.; Fieguth, A.; Fiorucci, S.; Fischer, H.; Flaecher, H.; Flierman, M.; Florek, T.; Foot, R.; Fox, P.J.; Franceschini, R.; Fraser, E.D.; Frenk, C.S.; Frohlich, S.; Fruth, T.; Fulgione, W.; Fuselli, C.; Gaemers, P.; Gaior, R.; Gaitskell, R.J.; Galloway, M.; Gao, F.; Garcia, I. Garcia; Genovesi, J.; Ghag, C.; Ghosh, S.; Gibson, E.; Gil, W.; Giovagnoli, D.; Girard, F.; Glade-Beucke, R.; Glück, F.; Gokhale, S.; Gouvêa, A. de; Gráf, L.; Grandi, L.; Grigat, J.; Grinstein, B.; Grinten, M.G.D. van der; Grössle, R.; Guan, H.; Guida, M.; Gumbsheimer, R.; Gwilliam, C. B.; Hall, C.R.; Hall, L.J.; Hammann, R.; Han, K.; Hannen, V.; Hansmann-Menzemer, S.; Harata, R.; Hardin, S.P.; Hardy, E.; Hardy, C.A.; Harigaya, K.; Harnik, R.; Haselschwardt, S.J.; Hernandez, M.; Hertel, S.A.; Higuera, A.; Hils, C.; Hochrein, S.; Hoetzsch, L.; Hoferichter, M.; Hood, N.; Hooper, D.; Horn, M.; Howlett, J.; Huang, D.Q.; Huang, Y.; Hunt, D.; Iacovacci, M.; Iaquaniello, G.; Ide, R.; Ignarra, C.M.; Iloglu, G.; Itow, Y.; Jacquet, E.; Jahangir, O.; Jakob, J.; James, R.S.; Jansen, A.; Ji, W.; Ji, X.; Joerg, F.; Johnson, J.; Joy, A.; Kaboth, A.C.; Kalhor, L.; Kamaha, A.C.; Kanezaki, K.; Kar, K.; Kara, M.; Kato, N.; Kavrigin, P.; Kazama, S.; Keaveney, A.W.; Kellerer, J.; Khaitan, D.; Khazov, A.; Khundzakishvili, G.; Khurana, I.; Kilminster, B.; Kleifges, M.; Ko, P.; Kobayashi, M.; Kodroff, D.; Koltmann, G.; Kopec, A.; Kopmann, A.; Kopp, J.; Korley, L.; Kornoukhov, V.N.; Korolkova, E.V.; Kraus, H.; Krauss, L.M.; Kravitz, S.; Kreczko, L.; Kudryavtsev, V.A.; Kuger, F.; Kumar, J.; Paredes, B. López; LaCascio, L.; Laha, R.; Laine, Q.; Landsman, H.; Lang, R.F.; Leason, E.A.; Lee, J.; Leonard, D.S.; Lesko, K.T.; Levinson, L.; Levy, C.; Li, I.; Li, S.C.; Li, T.; Liang, S.; Liebenthal, C.S.; Lin, J.; Lin, Q.; Lindemann, S.; Lindner, M.; Lindote, A.; Linehan, R.; Lippincott, W.H.; Liu, X.; Liu, K.; Liu, J.; Loizeau, J.; Lombardi, F.; Long, J.; Lopes, M.I.; Asamar, E. Lopez; Lorenzon, W.; Lu, C.; Luitz, S.; Ma, Y.; Machado, P.A.N.; Macolino, C.; Maeda, T.; Mahlstedt, J.; Majewski, P.A.; Manalaysay, A.; Mancuso, A.; Manenti, L.; Manfredini, A.; Mannino, R.L.; Marangou, N.; March-Russell, J.; Marignetti, F.; Undagoitia, T. Marrodán; Martens, K.; Martin, R.; Martinez-Soler, I.; Masbou, J.; Masson, D.; Masson, E.; Mastroianni, S.; Mastronardi, M.; Matias-Lopes, J.A.; McCarthy, M.E.; McFadden, N.; McGinness, E.; McKinsey, D.N.; McLaughlin, J.; McMichael, K.; Meinhardt, P.; Menéndez, J.; Meng, Y.; Messina, M.; Midha, R.; Milisavljevic, D.; Miller, E.H.; Milosevic, B.; Milutinovic, S.; Mitra, S.A.; Miuchi, K.; Mizrachi, E.; Mizukoshi, K.; Molinario, A.; Monte, A.; Monteiro, C.M.B.; Monzani, M.E.; Moore, J.S.; Morå, K.; Morad, J.A.; Mendoza, J.D. Morales; Moriyama, S.; Morrison, E.; Morteau, E.; Mosbacher, Y.; Mount, B.J.; Mueller, J.; Murphy, A. St J.; Murra, M.; Naim, D.; Nakamura, S.; Nash, E.; Navaieelavasani, N.; Naylor, A.; Nedlik, C.; Nelson, H.N.; Neves, F.; Newstead, J.L.; Ni, K.; Nikoleyczik, J.A.; Niro, V.; Oberlack, U.G.; Obradovic, M.; Odgers, K.; O’Hare, C.A.J.; Oikonomou, P.; Olcina, I.; Oliver-Mallory, K.; Oranday, A.; Orpwood, J.; Ostrovskiy, I.; Ozaki, K.; Paetsch, B.; Pal, S.; Palacio, J.; Palladino, K.J.; Palmer, J.; Panci, P.; Pandurovic, M.; Parlati, A.; Parveen, N.; Patton, S.J.; Pěč, V.; Pellegrini, Q.; Penning, B.; Pereira, G.; Peres, R.; Perez-Gonzalez, Y.; Perry, E.; Pershing, T.; Petrossian-Byrne, R.; Pienaar, J.; Piepke, A.; Pieramico, G.; Pierre, M.; Piotter, M.; Pizzella, V.; Plante, G.; Pollmann, T.; Porzio, D.; Qi, J.; Qie, Y.; Qin, J.; Quevedo, F.; Raj, N.; Silva, M. Rajado; Ramanathan, K.; García, D. Ramírez; Ravanis, J.; Redard-Jacot, L.; Redigolo, D.; Reichard, S.; Reichenbacher, J.; Rhyne, C.A.; Richards, A.; Riffard, Q.; Rischbieter, G.R.C.; Rocchetti, A.; Rosenfeld, S. L.; Rosero, R.; Rupp, N.; Rushton, T.; Saha, S.; Salucci, P.; Sanchez, L.; Sanchez-Lucas, P.; Santone, D.; Santos, J.M.F. dos; Sarnoff, I.; Sartorelli, G.; Sazzad, A.B.M.R.; Scheibelhut, M.; Schnee, R.W.; Schrank, M.; Schreiner, J.; Schulte, P.; Schulte, D.; Eissing, H. Schulze; Schumann, M.; Schwemberger, T.; Schwenk, A.; Schwetz, T.; Lavina, L. Scotto; Scovell, P.R.; Sekiya, H.; Selvi, M.; Semenov, E.; Semeria, F.; Shagin, P.; Shaw, S.; Shi, S.; Shockley, E.; Shutt, T.A.; Si-Ahmed, R.; Silk, J.J.; Silva, C.; Silva, M.C.; Simgen, H.; Šimkovic, F.; Sinev, G.; Singh, R.; Skulski, W.; Smirnov, J.; Smith, R.; Solmaz, M.; Solovov, V.N.; Sorensen, P.; Soria, J.; Sparmann, T.J.; Stancu, I.; Steidl, M.; Stevens, A.; Stifter, K.; Strigari, L.E.; Subotic, D.; Suerfu, B.; Suliga, A.M.; Sumner, T.J.; Szabo, P.; Szydagis, M.; Takeda, A.; Takeuchi, Y.; Tan, P.-L.; Taricco, C.; Taylor, W.C.; Temples, D.J.; Terliuk, A.; Terman, P.A.; Thers, D.; Thieme, K.; Thümmler, T.; Tiedt, D.R.; Timalsina, M.; To, W.H.; Toennies, F.; Tong, Z.; Toschi, F.; Tovey, D.R.; Tranter, J.; Trask, M.; Trinchero, G.C.; Tripathi, M.; Tronstad, D.R.; Trotta, R.; Tsai, Y.D.; Tunnell, C.D.; Turner, W.G.; Ueno, R.; Urquijo, P.; Utku, U.; Vaitkus, A.; Valerius, K.; Vassilev, E.; Vecchi, S.; Velan, V.; Vetter, S.; Vincent, A.C.; Vittorio, L.; Volta, G.; Krosigk, B. von; Piechowski, M. von; Vorkapic, D.; Wagner, C.E.M.; Wang, A.M.; Wang, B.; Wang, Y.; Wang, W.; Wang, J.J.; Wang, L.-T.; Wang, M.; Wang, Y.; Watson, J.R.; Wei, Y.; Weinheimer, C.; Weisman, E.; Weiss, M.; Wenz, D.; West, S.M.; Whitis, T.J.; Williams, M.; Wilson, M.J.; Winkler, D.; Wittweg, C.; Wolf, J.; Wolf, T.; Wolfs, F.L.H.; Woodford, S.; Woodward, D.; Wright, C.J.; Wu, V.H.S.; Wu, P.; Wüstling, S.; Wurm, M.; Xia, Q.; Xiang, X.; Xing, Y.; Xu, J.; Xu, Z.; Xu, D.; Yamashita, M.; Yamazaki, R.; Yan, H.; Yang, L.; Yang, Y.; Ye, J.; Yeh, M.; Young, I.; Yu, H.B.; Yu, T.T.; Yuan, L.; Zavattini, G.; Zerbo, S.; Zhang, Y.; Zhong, M.; Zhou, N.; Zhou, X.; Zhu, T.; Zhu, Y.; Zhuang, Y.; Zopounidis, J.P.; Zuber, K.; Zupan, J.
The nature of dark matter and properties of neutrinos are among the most pressing issues in contemporary particle physics. The dual-phase xenon time-projection chamber is the leading technology to cover the available parameter space for weakly interacting massive particles, while featuring extensive sensitivity to many alternative dark matter candidates. These detectors can also study neutrinos through neutrinoless double-beta decay and through a variety of astrophysical sources. A next-generation xenon-based detector will therefore be a true multi-purpose observatory to significantly advance particle physics, nuclear physics, astrophysics, solar physics, and cosmology. This review article presents the science cases for such a detector.
A probable Keplerian disk feeding an optically revealed massive young star
(Springer Nature, 2024) McLeod, Anna F.; Klaassen, Pamela D.; Reiter, Megan; Henshaw, Jonathan; Kuiper, Rolf; Ginsburg, Adam
The canonical picture of star formation involves disk-mediated accretion, with Keplerian accretion disks and associated bipolar jets primarily observed in nearby, low-mass young stellar objects (YSOs). Recently, rotating gaseous structures and Keplerian disks have been detected around several massive (M > 8 M⊙) YSOs (MYSOs)1–4, including several disk-jet systems5–7. All the known MYSO systems are in the Milky Way, and all are embedded in their natal material. Here we report the detection of a rotating gaseous structure around an extragalactic MYSO in the Large Magellanic Cloud. The gas motion indicates that there is a radial flow of material falling from larger scales onto a central disk-like structure. The latter exhibits signs of Keplerian rotation, so that there is a rotating toroid feeding an accretion disk and thus the growth of the central star. The system is in almost all aspects comparable to Milky Way high-mass YSOs accreting gas from a Keplerian disk. The key difference between this source and its Galactic counterparts is that it is optically revealed rather than being deeply embedded in its natal material as is expected of such a massive young star. We suggest that this is the consequence of the star having formed in a low-metallicity and low-dust content environment. Thus, these results provide important constraints for models of the formation and evolution of massive stars and their circumstellar disks.
A room-temperature mid-infrared photodetector for on-chip molecular vibrational spectroscopy
(AIP Publishing, 2018) Zheng, Bob; Zhao, Hangqi; Cerjan, Ben; Yazdi, Sadegh; Ringe, Emilie; Nordlander, Peter; Halas, Naomi J.; Laboratory for Nanophotonics
Infrared (IR) photodetection is of major scientific and technical interest since virtually all molecules exhibit characteristic vibrational modes in the mid-infrared region of the spectrum, giving rise to molecular spectroscopy and chemical imaging in this wavelength range. High-resolution IR spectroscopies, such as Fourier Transform IR spectroscopy, typically require large, bulky optical measurement systems and expensive photodetector components. Here, we present a high-responsivity photodetector for the mid-IR spectral region which operates at room temperature. Fabricated from silicon and aluminum, the photodetection mechanism is based on free carrier absorption, giving rise to a photoresponse rivalling commercially available cooled IR photodetectors. We demonstrate that infrared spectra of molecules deposited on this detector can be obtained by a direct electrical read-out. This work could pave the way for simple, fully integrated chemical sensors and other applications, such as chemical imaging, which would benefit from the combination of mid-IR detection, room-temperature operation, and ultracompact portability.
A search for decays of the Higgs boson to invisible particles in events with a top-antitop quark pair or a vector boson in proton-proton collisions at $$\sqrt{s} = 13\,\text {Te}\hspace{-.08em}\text {V} $$
(Springer Nature, 2023) CMS Collaboration
A search for decays to invisible particles of Higgs bosons produced in association with a top-antitop quark pair or a vector boson, which both decay to a fully hadronic final state, has been performed using proton-proton collision data collected at $${\sqrt{s}=13\,\text {Te}\hspace{-.08em}\text {V}}$$by the CMS experiment at the LHC, corresponding to an integrated luminosity of 138$$\,\text {fb}^{-1}$$. The 95% confidence level upper limit set on the branching fraction of the 125$$\,\text {Ge}\hspace{-.08em}\text {V}$$Higgs boson to invisible particles, $${\mathcal {B}({\textrm{H}} \rightarrow \text {inv})}$$, is 0.54 (0.39 expected), assuming standard model production cross sections. The results of this analysis are combined with previous $${\mathcal {B}({\textrm{H}} \rightarrow \text {inv})}$$searches carried out at $${\sqrt{s}=7}$$, 8, and 13$$\,\text {Te}\hspace{-.08em}\text {V}$$in complementary production modes. The combined upper limit at 95% confidence level on $${\mathcal {B}({\textrm{H}} \rightarrow \text {inv})}$$is 0.15 (0.08 expected).
A SEARCH FOR GIANT PLANET COMPANIONS TO T TAURI STARS
(The American Astronomical Society, 2012) Crockett, Christopher J.; Mahmud, Naved I.; Prato, L.; Johns-Krull, Christopher M.; Jaffe, Daniel T.; Hartigan, Patrick M.; Beichman, Charles A.
We present results from an ongoing multiwavelength radial velocity (RV) survey of the Taurus–Auriga star-forming region as part of our effort to identify pre-main-sequence giant planet hosts. These 1–3 Myr old T Tauri stars present significant challenges to traditional RV surveys. The presence of strong magnetic fields gives rise to large, cool star spots. These spots introduce significant RV jitter which can mimic the velocity modulation from a planet-mass companion. To distinguish between spot-induced and planet-induced RV modulation, we conduct observations at ∼6700Åand∼2.3μmand measure thewavelength dependence (if any) in theRVamplitude. CSHELL observations of the known exoplanet host Gl 86 demonstrate our ability to detect not only hot Jupiters in the near-infrared but also secular trends from more distant companions. Observations of nine very young stars reveal a typical reduction in RV amplitude at the longer wavelengths by a factor of ∼2–3. While we cannot confirm the presence of planets in this sample, three targets show different periodicities in the two wavelength regions. This suggests different physical mechanisms underlying the optical and the K-band variability.
A search for new physics in central exclusive production using the missing mass technique with the CMS detector and the CMS-TOTEM precision proton spectrometer
(Springer Nature, 2023) CMS Collaboration
A generic search is presented for the associated production of a Z boson or a photon with an additional unspecified massive particle X, $${\textrm{pp}}\rightarrow {\textrm{pp}} +{{\textrm{Z}}}/\upgamma +{{\textrm{X}}} $$, in proton-tagged events from proton–proton collisions at $$\sqrt{s}=13\, \textrm{TeV}$$, recorded in 2017 with the CMS detector and the CMS-TOTEM precision proton spectrometer. The missing mass spectrum is analysed in the 600–1600 GeV range and a fit is performed to search for possible deviations from the background expectation. No significant excess in data with respect to the background predictions has been observed. Model-independent upper limits on the visible production cross section of $${\textrm{pp}}\rightarrow {\textrm{pp}} +{{\textrm{Z}}}/\upgamma +{{\textrm{X}}} $$are set.
A search for pair production of new light bosons decaying into muons
(Elsevier, 2016) CMS Collaboration
A search for the pair production of new light bosons, each decaying into a pair of muons, is performed with the CMS experiment at the LHC, using a dataset corresponding to an integrated luminosity of 20.7 fb−1 collected in proton–proton collisions at center-of-mass energy of s=8 TeV. No excess is observed in the data relative to standard model background expectation and a model independent upper limit on the product of the cross section, branching fraction, and acceptance is derived. The results are compared with two benchmark models, the first one in the context of the next-to-minimal supersymmetric standard model, and the second one in scenarios containing a hidden sector, including those predicting a nonnegligible light boson lifetime.

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