Probing the interior of Earth using oscillating neutrinos at INO-ICAL

Atmospheric neutrinos offer the possibility of exploring the internal structure of Earth. This information is complementary to the traditional probes of seismic and gravitational studies. While propagating through Earth, the multi-GeV neutrinos encounter the Earth's matter effects due to the coherent forward scattering with the ambient electrons, which alters the neutrino oscillation probabilities. We present how well an atmospheric neutrino oscillation experiment like the 50 kt Iron Calorimeter (ICAL) detector at India-based Neutrino Observatory would validate the presence of Earth's core, measure the location of the core-mantle boundary (CMB), and probe the dark matter (DM) inside the Earth in a unique way through Earth matter effects in neutrino oscillations. Owing to good angular resolution, ICAL can observe the core-passing neutrinos efficiently. Due to its magnetized setup, it would be able to observe neutrinos and antineutrinos separately. With 500 kt$\cdot$yr exposure, the presence of Earth's core can be independently confirmed at ICAL with a median $\Delta\chi^2$ of 7.45 (4.83) for normal (inverted) mass ordering. With 1000 kt$\cdot$yr exposure, ICAL would be able to locate the CMB with a precision of about $\pm$ 250 km at $1\sigma$. It would also be sensitive to the possible presence of dark matter with 3.5% of the mass of Earth at $1\sigma$. The charge identification capability of ICAL would play an important role in achieving these precisions.Comment: 4 pages, 2 figures; contribution to proceedings of The European Physical Society Conference on High Energy Physics (EPS-HEP2023

A high pressure XRD setup at ADXRD beamline (BL-12) on Indus-2

A high pressure XRD measurement setup in the angle dispersive geometry has been setup in the Angle Dispersive X-ray diffraction beamline (BL-12) in Indus-2 synchrotron facility. The X-ray beam is collimated inside the Diamond Anvil Cell (DAC) using a pair of cross-slit collimators and 100 micron orifice in a 400 micron thick Ta sheet. With the use of an adaptive optics to ensure a converging beam at the sample position, the need of an X-ray beam collimator is eliminated making the alignment of the DAC quite easy. The alignment of the DAC with respect to the incident X-ray beam is made by placing it on a computer controlled sample mounting and alignment stage developed specifically for this setup. Interactive software has been developed to make the alignment of the X-ray through the DAC very easy and accurate. NIST standard LaB6 powder was used for test runs, and a few fine pieces of gold served as pressure calibrator. The data was recorded on a MAR345 Image plate detector

Determination of ethambutol MICs for Mycobacterium tuberculosis and Mycobacterium avium isolates by resazurin microtitre assay

Objectives: To test susceptibilities of Mycobacterium tuberculosis (MTB) isolates to ethambutol by the Lowenstein-Jensen (LJ) proportion method and resazurin microtitre assay (REMA) and to evaluate REMA for the determination of ethambutol MICs for MTB and Mycobacterium avium isolates. Methods: A total of 50 MTB and 20 M. avium isolates were tested to determine the MICs of ethambutol by REMA and agar dilution method. MTB isolates were also tested by the LJ proportion method. Results: REMA provided ethambutol susceptibility results for all the isolates within 8-9 days. For MTB isolates, REMA showed 96.7% sensitivity, 100.0% specificity and 98.0% accuracy when LJ proportion results were taken as 'gold standard'. For both MTB and M. avium isolates, the MICs determined by REMA were lower than those determined in agar medium, indicating that MIC values determined by REMA are closer to the actual MICs for the isolates. Conclusions: REMA can be used as a rapid and inexpensive method for mycobacterial drug susceptibility testing against ethambutol. In comparison with the agar method, the MICs determined by REMA can more accurately be correlated with achievable plasma concentrations of antimycobacterial agents

Galactic Core-Collapse Supernovae at IceCube: “Fire Drill” Data Challenges and follow-up

The next Galactic core-collapse supernova (CCSN) presents a once-in-a-lifetime opportunity to make astrophysical measurements using neutrinos, gravitational waves, and electromagnetic radiation. CCSNe local to the Milky Way are extremely rare, so it is paramount that detectors are prepared to observe the signal when it arrives. The IceCube Neutrino Observatory, a gigaton water Cherenkov detector below the South Pole, is sensitive to the burst of neutrinos released by a Galactic CCSN at a level >10σ. This burst of neutrinos precedes optical emission by hours to days, enabling neutrinos to serve as an early warning for follow-up observation. IceCube\u27s detection capabilities make it a cornerstone of the global network of neutrino detectors monitoring for Galactic CCSNe, the SuperNova Early Warning System (SNEWS 2.0). In this contribution, we describe IceCube\u27s sensitivity to Galactic CCSNe and strategies for operational readiness, including "fire drill" data challenges. We also discuss coordination with SNEWS 2.0

All-Energy Search for Solar Atmospheric Neutrinos with IceCube

The interaction of cosmic rays with the solar atmosphere generates a secondary flux of mesons that decay into photons and neutrinos – the so-called solar atmospheric flux. Although the gamma-ray component of this flux has been observed in Fermi-LAT and HAWC Observatory data, the neutrino component remains undetected. The energy distribution of those neutrinos follows a soft spectrum that extends from the GeV to the multi-TeV range, making large Cherenkov neutrino telescopes a suitable for probing this flux. In this contribution, we will discuss current progress of a search for the solar neutrino flux by the IceCube Neutrino Observatory using all available data since 2011. Compared to the previous analysis which considered only high-energy muon neutrino tracks, we will additionally consider events produced by all flavors of neutrinos down to GeV-scale energies. These new events should improve our analysis sensitivity since the flux falls quickly with energy. Determining the magnitude of the neutrino flux is essential, since it is an irreducible background to indirect solar dark matter searches

TXS 0506+056 with Updated IceCube Data

Past results from the IceCube Collaboration have suggested that the blazar TXS 0506+056 is a potential source of astrophysical neutrinos. However, in the years since there have been numerous updates to event processing and reconstruction, as well as improvements to the statistical methods used to search for astrophysical neutrino sources. These improvements in combination with additional years of data have resulted in the identification of NGC 1068 as a second neutrino source candidate. This talk will re-examine time-dependent neutrino emission from TXS 0506+056 using the most recent northern-sky data sample that was used in the analysis of NGC 1068. The results of using this updated data sample to obtain a significance and flux fit for the 2014 TXS 0506+056 "untriggered" neutrino flare are reported