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The Pierre Auger Observatory (Auger) and the Telescope Array (TA) are the world's two largest ultra-high-energy cosmic ray (UHECR) observatories. They operate in the Southern and Northern hemispheres, respectively, at similar latitudes but with distinct surface detector (SD) designs. A significant challenge in studying UHECR physics across the full sky is the apparent discrepancy in flux measurements between the two experiments. This discrepancy could arise from astrophysical differences and/or systematic effects related to their detector designs and sensitivities to extensive air shower components. To address this, the Auger@TA working group aims to cross-calibrate the two observatories with a self-triggering micro-Auger array within the TA array. This micro-array consists of eight Auger Surface Detector (SD) stations equipped with Water Cherenkov Detectors (WCDs) and AugerPrime Surface Scintillator Detectors. Seven SD stations, configured with a centered-1-PMT design, are arranged in a hexagonal pattern with one station in the center, with 1.5 km spacing, mirroring the Auger layout. The eighth station, which features a standard 3-PMT Auger station, is located in conjunction with a TA detector at the center of the hexagon, forming a triplet for high-statistics and low-uncertainty cross-calibration. A custom communication system that uses readily available components enables seamless communication between stations and remote access to each station through a central computer. The micro-array is now fully deployed, and initial data-taking is about to start. This presentation will detail the instrumentation, communication systems, central data acquisition system, expected performance of the micro-array, and preliminary results as appropriate. 

Abstract Molecular observations of four planetary nebulae (PNe), M4-17, Hu 1-1, M1-59, and Na 2, were conducted at 1–3 mm using the Arizona Radio Observatory’s 12 m antenna and Submillimeter Telescope, and the Institut de Radioastronomie Millimétrique 30 m Telescope. Toward M4-17, HNC (J= 3 → 2), CCH (N= 2 → 1,N= 3 → 2), CN (N= 1 → 0,N= 2 → 1), H₂CO (J_Ka,Kc= 2_1,2→ 1_1,1,J_Ka,Kc= 2_0,2→ 1_0,1,J_Ka,Kc= 2_1,1→ 1_1,0), CS (J= 3 → 2,J= 5 → 4), and H¹³CN (J= 2 → 1) were detected. An almost identical set of transitions was identified toward Hu 1-1. Moreover, c–C₃H₂was detected in Hu 1-1 via three 2 mm lines:J_Ka,Kc= 3_1,2→ 2_2,1,J_Ka,Kc= 4_1,4→ 3_0,3, andJ_Ka,Kc= 3_{2, 2}→ 2_1,1. HNC, CCH, CN, CS, and H¹³CN were found in M1-59, as well as H₂S via itsJ_Ka,Kc= 1_1,0→ 1_0,1line—the first detection of this key sulfur species in PNe. In addition, CCH and CN were identified in the 27,000 yr old Na 2. Among these four sources, CN and CCH were the most prevalent molecules (after CO and H₂) with fractional abundances, relative to H₂, off∼ 0.9–7.5 × 10⁻⁷and 0.8–7.5 × 10⁻⁷, respectively. CS and HNC have abundances in the rangef∼ 0.5–5 × 10⁻⁸, the latter resulting in HCN/HNC ∼ 3 across all three PNe. The unusual species H₂CO, c–C₃H₂, and H₂S hadf∼ 3–4 × 10⁻⁷, 10⁻⁸, and 6 × 10⁻⁸. This study suggests that elliptical PNe such as Hu 1-1 can have a diverse molecular composition. The presence of CN, CCH, and HCO⁺in Na 2, with comparable abundances to younger PNe, demonstrates that molecular content is maintained into the late PN stage. 

We present experimental results of high-harmonic generation (HHG) driven by a 1300 nm beam in three different polarization states: linear, radial, and azimuthal. We found that the optimal pressure for phase matching was roughly twice as high for the vector beam drivers than the linear driver. We attribute this difference in pressure primarily to the Gouy phase, which differs by a factor of two between the linear and vector polarization states. We demonstrate a target for HHG that produces a uniform pressure profile in the interaction region that is nearly identical to the backing pressure and preserves the mode of the driving beam. We provide characterization and validation of this technique through flow simulations and experimental measurements. 

Abstract Despite model predictions, many planetary nebulae appear to have a relatively rich molecular content. Observational studies of over 30 such objects show the presence of a variety of gas-phase molecules, from simple species such as CN and CS, to more complex organics including H₂CO, HC₃N, c-C₃H₂, and CH₃CN. Other PNe contain fullerenes; carbonaceous and silicate dust features are also found. Molecular abundances also do not appear to vary with nebular age. Remnant material from the asymptotic giant branch appears to undergo chemical processing in the protoplanetary nebula phase and then is frozen out in planetary nebulae. PN ejecta are thus in part molecular in content and may account for the observation of complex molecules in diffuse clouds. 

We present the limits on noise for the readout of cryogenic high-Q resonators using dc Superconducting Quantum Interference Devices (SQUIDs) below 300 MHz. This analysis uses realized first-stage SQUIDs (previously published), whose performance is well described by Tesche–Clarke (TC) theory, coupled directly to the resonators. We also present data from a prototype second-stage dc SQUID array designed to couple to this first-stage SQUID as a follow-on amplifier with high system bandwidth. This analysis is the first full consideration of dc SQUID noise performance referred to a high-Q resonator over this frequency range and is presented relative to the standard quantum limit. We include imprecision, backaction, and backaction–imprecision noise correlations from TC theory, the noise contributed by the second-stage SQUIDs, wiring, and preamplifiers, and optimizations for both on-resonance measurements and off-resonance scan sensitivity. This architecture has modern relevance due to the increased interest in axion searches and the requirements of the DMRadio-m3 axion search, which uses dc SQUIDs in this frequency range. 

Abstract Observations of HCN and HCO + have been carried out toward 13 planetary nebulae (PNe) using the facilities of the Arizona Radio Observatory (ARO). These nebulae represent a wide range of morphologies and ages (∼2000–28,000 yr). For both molecules, the J = 1 → 0 transitions at 88–89 GHz and the J = 3 → 2 lines at 265–267 GHz were measured, together with CO lines ( J = 1 → 0, 2 → 1, and 3 → 2, depending on the source), using the ARO 12 m and Submillimeter Telescopes. HCN and HCO + were detected with at least one transition in 10 nebulae: He 2-459, Hu 1-1, K3-52, K3-65, M1-8, M1-40, M1-59, M2-53, M4-17, and NGC 6445. HCO + was additionally identified via two transitions in Na 2. Some observed line profiles were complex, with multiple velocity components tracing varied outflows. From radiative transfer modeling, column densities were established for HCN and HCO + : N tot (HCN) = 0.005–1.1 × 10 14 and N tot (HCO + ) = 0.008–9.5 × 10 13 cm −2 . Gas densities of n (H 2 ) ∼ 10 5 –10 7 cm −3 were also determined for all PNe. Fractional abundances with respect to H 2 , calculated using CO as a proxy, are f (HCN) ∼ 0.2–1.5 × 10 −7 and f (HCO + ) ∼ 0.3–5.1 × 10 −8 . The abundances of HCN and HCO + did not significantly vary with nebular age to 28,000 yr. Combined with previous observations, at least 30 PNe contain HCN and/or HCO + , indicating that polyatomic molecules are common constituents of these objects. The data strongly support a scenario where dense ejecta from PNe seed the interstellar medium with molecular material. 

Grading adhesive properties across a bondline can lead to more unniform stresses and increased strength without altering the geometry of the adherends. In this research, radiation sensitizers have been added to adhesives to create a secondary cross-linking possibility that is activated with radiation. In this way the adhesive stiffness and strength can be controlled by controlling the exposure to radition. In this paper, a system of grading adhesive properties is introduced and the double cantilver beam test results show that the gradation not only changes stiffness and strength, but also mode I fracture properties. Additionally, specimens were created with graded properties along the bondline and test results will be presented in the final paper. 

Abstract The Auger Engineering Radio Array (AERA) measures radio emission from high-energy extensive air showers. Consisting of 153 autonomous radio-detector stations spread over 17 km^2, it detects radio waves in the frequency range of 30 to 80 MHz. Accurate characterization of the detector response is crucial for proper interpretation of the collected data. Previously, this was achieved through laboratory measurements of the analog chain and simulations and measurements of the antenna's directional response. In this paper, we perform an absolute calibration using the continuously monitored sidereal modulation of the diffuse Galactic radio emission. Calibration is done by comparing the average frequency spectra recorded by the stations with predictions from seven different models of the full radio sky, accounting for the system response, which includes the antenna, filters, and amplifiers. The analysis of the calibration constants over a period of seven years shows no relevant and no significant ageing effect in the AERA antennas. This result confirms the long-term stability of the detector stations and demonstrates the possibility for a radio detector to effectively monitor ageing effects of other detectors operating over extended periods.