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Quantum computers are projected to be able to carry out certain complex calculations that our current, classical computers cannot accomplish efficiently. The word quantum refers to the smallest possible unit of something, which in this context relates to the properties of tiny particles like atoms, electrons, and photons. Quantum computers use these properties to perform complex calculations in ways that are fundamentally different from non-quantum computers. In , quantum computers will be faster than classical computers. A quantum computing revolution requires a new generation of scientists and engineers who are familiar with quantum concepts and principles. Yet, educational efforts to teach the basic concepts of this field to a new generation are lacking [2]. A few efforts have been developed to introduce pre-college students to QIS, including an activity on quantum teleportation for secondary school students [3] and a series of coding-based activities for high-school students [4]. However, high-quality activities to promote QIS at the K-12 level are scarce, despite research showing that middle school is a crucial time for students as they begin to contemplate possible career paths [5,6]. This article describes the adaptation of an existing online educational computer game to introduce quantum computing concepts to an interactive science center audience from age seven to adult 

Low-density meter-scale plasma waveguides produced in meter-scale supersonic gas jets have paved the way for recent demonstrations of all-optical multi-gigaelectronvolt laser wakefield acceleration (LWFA). This paper reviews recent advances by the University of Maryland, which have enabled these results, focusing on the development of elongated supersonic gas jets up to ∼1 m in length, experimental and simulation studies of plasma waveguide formation, and a new three-stage model for relativistic pulse propagation dynamics in these waveguides. We also present results from recent LWFA experiments conducted at the Laboratory for Advanced Lasers and Extreme Photonics at Colorado State University demonstrating high charge, low divergence electron bunches to ∼10 GeV, with laser-to-electron beam efficiency of at least ∼30%. 

Context. Sensitive radio continuum data could bring the number of known supernova remnants (SNRs) in the Galaxy more in line with what is expected. Due to confusion in the Galactic plane, however, faint SNRs can be challenging to distinguish from brighter HIIregions and filamentary radio emission. Aims. We exploited new 1.3 GHz SARAO MeerKAT Galactic Plane Survey (SMGPS) radio continuum data, which cover 251° ≤ℓ≤ 358° and 2° ≤ℓ≤ 61° at |b| ≤ 1.5°, to search for SNR candidates in the Milky Way disk. Methods. We also used mid-infrared data from theSpitzerGLIMPSE,SpitzerMIPSGAL, and WISE surveys to help identify SNR candidates. These candidates are sources of extended radio continuum emission that lack mid-infrared counterparts, are not known as HIIregions in the WISE Catalog of Galactic HIIRegions, and have not been previously identified as SNRs. Results. We locate 237 new Galactic SNR candidates in the SMGPS data. We also identify and confirm the expected radio morphology for 201 objects classified in the literature as SNRs and 130 previously identified SNR candidates. The known and candidate SNRs have similar spatial distributions and angular sizes. Conclusions. The SMGPS data allowed us to identify a large population of SNR candidates that can be confirmed as true SNRs using radio polarization measurements or by deriving radio spectral indices. If the 237 candidates are confirmed as true SNRs, it would approximately double the number of known Galactic SNRs in the survey area, alleviating much of the discrepancy between the known and expected populations. 

Type IIb supernovae (SNe IIb) are core-collapse events whose optical spectra show strong hydrogen features that disappear over time, implying that their progenitors were nearly, but not completely, stripped of their hydrogen envelopes prior to core collapse. Thus, compared to hydrogen-rich SNe II, SNe IIb can provide a closer examination of the underlying structure of the progenitor system, particularly during early photospheric phases (less than +70 days relative to max. light). I will present early-time multi-epoch optical spectropolarimetry of several SNe IIb, obtained using the SPOL instrument at the University of Arizona. Using polarization diagnostics provides a way to track structural changes in the depleted hydrogen envelopes of these SNe as deeper layers of helium and other elements emerge and evolve. I find significant temporal polarization increases in the absorption wings of their H and He lines. Some of these line features make "loops" in Stokes Q-U diagrams, suggesting non-axisymmetic structure in the ejecta, perhaps arising from a transient absorbing clump. Furthermore, the majority of these SNe show polarimetric evidence for aspherical explosions along a preferred, or dominant, axis. I discuss the implications these findings have on the 3D geometry of the explosions by comparing the observed polarization to published synthetic spectropolarimetry that models axial symmetry and clump structures in stripped-envelope, core-collapse SNe. This comparative study naturally facilitates a broader discussion around the unresolved question as to what extent this SNe subclass shows common polarization characteristics. 

Abstract We present multi-epoch optical spectropolarimetric and imaging polarimetric observations of the nearby Type II supernova (SN) 2023ixf discovered in M101 at a distance of 6.85 Mpc. The first imaging polarimetric observations were taken +2.33 days (60085.08 MJD) after the explosion, while the last imaging polarimetric data points (+73.19 and +76.19 days) were acquired after the fall from the light-curve plateau. At +2.33 days there is strong evidence of circumstellar material (CSM) interaction in the spectra and the light curve. A significant level of intrinsic polarizationp_r = 1.02% ± 0.07% is seen during this phase, which indicates that this CSM is aspherical. We find that the polarization evolves with time toward the interstellar polarization level during the photospheric phase, which suggests that the recombination photosphere is spherically symmetric. There is a jump in polarization (p_r = 0.45% ± 0.08% andp_r = 0.62% ± 0.08%) at +73.19 and +76.19 days when the light curve falls from the plateau. This is a phase where polarimetric data are sensitive to nonspherical inner ejecta or a decrease in optical depth into the single-scattering regime. We also present spectropolarimetric data that reveal line (de)polarization during most of the observed epochs. In addition, at +14.50 days we see an “inverse P Cygni” profile in the H and He line polarization, which clearly indicates the presence of asymmetrically distributed material overlying the photosphere. The overall temporal evolution of the polarization is typical for Type II SNe, but the high level of polarization during the rising phase has only been observed in SN 2023ixf. 

Type Ia Supernovae (SNe Ia) arise from carbon oxygen white dwarfs, but the true nature of their progenitor systems and explosion mechanisms remains the subject of considerable debate. The various progenitor models and methods of ignition result in different ejecta morphologies and/or distributions of material. By observing the polarization of SNe spectra we can gather insight into the geometry of these explosions. A key diagnostic that appears to be correlated with other SN Ia properties is the change in polarization observed across the Si II 6355 Å feature near maximum light. To investigate this, we are undertaking a systematic analysis of this feature in a uniformly obtained sample of SNe Ia observed at multiple epochs as part of the Supernova Spectropolarimetry (SNSPOL) Project, which gathered data, from 2010-2018, using the CCD Imaging/Spectropolarimeter (SPOL) on the 61" Kuiper, 6.5 m MMT, and 90" Bok telescopes. Here we present a preliminary analysis of the Si II feature in a particularly well-observed object from our sample, SN 2018gv, and present 10 epochs of data spanning from 10 days before, to 22 days after, peak light. We compare our near-maximum SNSPOL data with complementary data presented by Yang et al. [1]. This work was supported by NSF grants AST-1210311 and AST-2010001, and NASA grant NNX15AU81G. References: [1] Yang, Yi et al. 2020, ApJ, 902. 

The data generated during additive manufacturing (AM) practice can be used to train machine learning (ML) tools to reduce defects, optimize mechanical properties, or increase efficiency. In addition to the size of the repository, emerging research shows that other characteristics of the data also impact suitability of the data for AM-ML application. What should be done in cases for which the data in too small, too homogeneous, or otherwise insufficient? Data augmentation techniques present a solution, offering automated methods for increasing the quality of data. However, many of these techniques were developed for machine vision tasks, and hence their suitability for AM data has not been verified. In this study, several data augmentation techniques are applied to synthetic design repositories to characterize if and to what degree they enhance their performance as ML training sets. We discuss the comparative advantage of these data augmentation techniques across several canonical AM-ML tasks. 

Type Ia Supernovae (SNe Ia) arise from carbon oxygen white dwarfs, but the true nature of their progenitor systems and explosion mechanisms remains the subject of considerable debate. The various progenitor models and methods of ignition result in different ejecta morphologies and/or distributions of material. By observing the polarization of SNe spectra we can gather insight into the geometry of these explosions. A key diagnostic that appears to be correlated with other SN Ia properties is the change in polarization observed across the Si II 6355 Å feature near maximum light. To investigate this, we are undertaking a systematic analysis of this feature in a uniformly obtained sample of SNe Ia observed at multiple epochs as part of the Supernova Spectropolarimetry (SNSPOL) Project, which gathered data, from 2010-2018, using the CCD Imaging/Spectropolarimeter (SPOL) on the 61" Kuiper, 6.5 m MMT, and 90" Bok telescopes. Here we present a preliminary analysis of the Si II feature in a particularly well-observed object from our sample, SN 2018gv, and present 10 epochs of data spanning from 10 days before, to 22 days after, peak light. We compare our near-maximum SNSPOL data with complementary data presented by Yang et al. [1]. This work was supported by NSF grants AST-1210311 and AST-2010001, and NASA grant NNX15AU81G. References: [1] Yang, Yi et al. 2020, ApJ, 902. 

ABSTRACT We present multi-epoch spectropolarimetry and spectra for a sample of 14 Type IIn supernovae (SNe IIn). We find that after correcting for likely interstellar polarization, SNe IIn commonly show intrinsic continuum polarization of 1–3 per cent at the time of peak optical luminosity, although a few show weaker or negligible polarization. While some SNe IIn have even stronger polarization at early times, their polarization tends to drop smoothly over several hundred days after peak. We find a tendency for the intrinsic polarization to be stronger at bluer wavelengths, especially at early times. While polarization from an electron scattering region is expected to be grey, scattering of SN light by dusty circumstellar material (CSM) may induce such a wavelength-dependent polarization. For most SNe IIn, changes in polarization degree and wavelength dependence are not accompanied by changes in the position angle, requiring that asymmetric pre-SN mass loss had a persistent geometry. While 2–3 per cent polarization is typical, about 30 per cent of SNe IIn have very low or undetected polarization. Under the simplifying assumption that all SN IIn progenitors have axisymmetric CSM (i.e. disc/torus/bipolar), then the distribution of polarization values we observe is consistent with similarly asymmetric CSM seen from a distribution of random viewing angles. This asymmetry has very important implications for understanding the origin of pre-SN mass loss in SNe IIn, suggesting that it was shaped by binary interaction.