The magnetised Iron Calorimeter detector at the India-based Neutrino Observatory (INO) has a unique feature to identify the neutrinos and antineutrinos on an event by event basis. This feature can be harnessed to detect the differences between the oscillation parameters of neutrinos and antineutrinos independently. In this paper, we analysed Charged Current $ν_μ$ and $\overlineν_μ$ events under the influence of earth matter effect using three neutrino flavor oscillation framework. If the atmospheric mass-squared differences and mixing parameters for neutrinos are different from antineutrinos, we present the prospects for the experimental observation of these differences in atmospheric $ν$ and $\overline ν_μ$ oscillations at INO. We estimate the detector sensitivity to confirm a non-zero difference in the mass-squared splittings ($|Δm^{2}_{32}|-|Δ\overline{m^{2}}_{32}|$) for neutrinos and antineutrinos.
We study the capability of INO-ICAL to determine the atmospheric neutrino oscillation parameters $|Δm^2_{31}|$ and $\sin^2 θ_{23}$. We do not use any generator level information. Instead, we process the generated atmospheric neutrino events through GEANT4 simulation of the detector and the event reconstruction framework. Among the outputs of this framework, only the momentum and direction of the longest track were used in a previous study by other authors. In this study, in addition to these variables, we consider a third variable based on additional hits, which arise due to hadrons in the eve…
We study the prospects of detecting muon events at the upcoming Iron CALorimeter (ICAL) detector to be built at the proposed India-based Neutrino Observatory (INO) facility due to neutrinos arising out of annihilation of Weakly Interactive Massive Particles (WIMP) in the centre of the earth. The atmospheric neutrinos coming from the direction of earth core presents an irreducible background. We consider 50kt $\times$ 10 years of ICAL running and WIMP masses between 10-100 GeV and present 90 \% C.L. exclusion sensitivity limits on $σ_{SI}$ which is the WIMP-nucleon Spin Independent (SI) interac…
The Iron Calorimeter (ICAL) detector at the proposed India-based Neutrino Observatory (INO) aims to detect atmospheric neutrinos and antineutrinos separately in the multi-GeV range of energies and over a wide range of baselines. By utilizing its charge identification capability, ICAL can efficiently distinguish $μ^-$ and $μ^+$ events. Atmospheric neutrinos passing long distances through Earth can be detected at ICAL with good resolution in energy and direction, which enables ICAL to see the density-dependent matter oscillations experienced by upward-going neutrinos in the multi-GeV range of en…
Sub-relativistic magnetic monopoles are predicted from the GUT era by theory. To date there have been no confirmed observations of such exotic particles. The Iron CALorimeter (ICAL) at India-based Neutrino Observatory (INO) aims to measure the neutrino oscillation parameters precisely. As it is a tracking detector there is also the possibility of detecting magnetic monopoles in the sub-relativistic region. Using ICAL the magnetic monopole event is characterised by the large time intervals of upto 30 microsec between the signals in successive layers of the active detectors. The aim of this stud…
We present the reach of the proposed INO-ICAL in measuring the atmospheric-neutrino-oscillation parameters $θ_{23}$ and $Δm^2_{32}$ using full event-by-event reconstruction for the first time. We also study the fluctuations in the data and their effect on the precision measurements and mass-hierarchy analysis for a five-year exposure of the 50 kton ICAL detector. We find a mean resolution of $Δχ^2 \approx 2.9$, which rules out the wrong mass hierarchy of the neutrinos with a significance of approximately $1.7σ$. These results are similar to those to presented earlier studies that approximated …
We perform a detailed analysis for the prospects of detecting active-sterile oscillations involving a light sterile neutrino, over a large $Δm^2_{41}$ range of $10^{-5}$ eV$^2$ to $10^2$ eV$^2$, using 10 years of atmospheric neutrino data expected from the proposed 50 kt magnetized ICAL detector at the INO. This detector can observe the atmospheric $ν_μ$ and $\barν_μ$ separately over a wide range of energies and baselines, making it sensitive to the magnitude and sign of $Δm^2_{41}$ over a large range. If there is no light sterile neutrino, ICAL can place competitive upper limit on $|U_{μ4}|^2…
The main aim of the ESS$ν$SB proposal is the discovery of the leptonic CP phase $δ_{CP}$ with a high significance ($5σ$ for 50% values of $δ_{CP}$) by utilizing the physics at the second oscillation maxima of the $P_{μe}$ channel. It can achieve $3σ$ sensitivity to hierarchy for all values of $δ_{CP}$. In this work, we concentrate on the hierarchy and octant sensitivity of the ESS$ν$SB experiment. We show that combining the ESS$ν$SB experiment with the atmospheric neutrino data from the proposed India-based Neutrino Observatory(INO) experiment can result in an increased sensitivity to mass hie…
The relatively large measured value of $θ_{13}$ has opened up the possibility of determining the neutrino mass hierarchy through earth matter effects. Amongst the current accelerator-based experiments only NOvA has a long enough baseline to observe earth matter effects. However, NOvA is plagued with uncertainty on the knowledge of the true value of $δ_{CP}$, and this could drastically reduce its sensitivity to the neutrino mass hierarchy. The earth matter effect on atmospheric neutrinos on the other hand is almost independent of $δ_{CP}$. The 50 kton magnetized Iron CALorimeter at the India-ba…
The India-based Neutrino Observatory (INO) will host a 50 kt magnetized iron calorimeter (ICAL) detector that will be able to detect muon tracks and hadron showers produced by Charged-Current muon neutrino interactions in the detector. The ICAL experiment will be able to determine the precision of atmospheric neutrino mixing parameters and neutrino mass hierarchy using atmospheric muon neutrinos through earth matter effect. In this paper, we report on the sensitivity for the atmospheric neutrino mixing parameters ($\sin^{2}θ_{23}$ and $|Δm^{2}_{32}|$) for the ICAL detector using the reconstruc…
India-based Neutrino Observatory (INO) is a planned neutrino experiment to be build up in southern part of India.The INO observatory will host a 51 kton Iron Calorimeter (ICAL) detector to detect atmospheric neutrinos. Resistive Plate Chamber (RPC) has been chosen as the active detector element for the ICAL experiment. The ICAL experiment will consist of about 28,000 RPC's of dimension $2~m\times 2~m$, divided into three modules. The experiment is planned to take data at least for 20 years from its start date. Due to the large number of RPC needed for ICAL experiment and the long lifetime of t…
The India-based Neutrino Observatory (INO) collaboration has chosen glass Resistive Plate Chambers (RPCs) as the active detector elements for the Iron Calorimeter (ICAL) experiment. In the present work, we study the electrical properties such as bulk resistivity and relative permittivity of the glasses from two different manufacturers and compared the performances of RPCs built using these glasses. We conclude that the glass electrodes with larger bulk resistivy and permittivity are better suited for manufacturing RPCs for the ICAL experiment, as these detectors could be operated at lower bias…
Glass based Resistive Plate Chambers (RPCs) are going to be used as an active element in the Iron Calorimeter (ICAL) experiment at the India based Neutrino Observatory (INO), which is being constructed to study atmospheric neutrinos. Though the RPC detector operational parameters are more or less finalized, the readout electronics is being developed using various technologies. The ICAL experiment will consist of about 29,000 RPC detectors of 2 m $\times$ 2 m in size with each detector having 64 readout channels both in the X and Y directions. The present study focusses on multi-channel electro…
We report on the simulation studies on the possibility of dark matter particle (DMP) decaying into leptonic modes. While not much is known about the properties of dark matter particles except through their gravitational effect, it has been recently conjectured that the so called "anomalous Kolar Events" observed some decades ago may be due to the decay of unstable dark matter particles (M.V.N. Murthy and G.Rajasekaran, Pramana, {\bf 82}, 609 (2014)). The aim of this study is to see if this conjecture can be verified at the proposed Iron Calorimeter (ICAL) detector at INO. We study the possible…
The Resistive Plate Chambers (RPCs) are going to be used as the active detectors in the India-based Neutrino Observatory (INO)-Iron Calorimeter (ICAL) experiment for the detection and study of atmospheric neutrinos. In this paper, an extensive study of structural and electrical properties for different kind of bakelite RPC electrodes is presented. RPCs fabricated from these electrodes are tested for their detector efficiency and noise rate. The study concludes with the variation of efficiency, leakage current and counting rate over the period of operation with different gas compositions and op…
The possibility of Lorentz Invariance Violation (LIV) may appear in unified theories, such as string theory, which allow the existence of a new space-time structure at the Planck scale ($M_p \sim 10^{19}$ GeV). This effect can be observed at low energies with a strength of $\sim 1/M_p$ using the perturbative approach. In the minimal Standard Model extension (SME) framework, the neutrino mass-induced flavor oscillation gets modified in the presence of LIV. The Iron Calorimeter (ICAL) detector at the proposed India-based Neutrino Observatory (INO) offers a unique window to probe these LIV parame…
The primary physics signal events in the ICAL at INO are the $ν_μ$ charged current (CC) interactions with a well defined muon track. Apart from these events, ICAL can also detect other types of neutrino interactions, i.e. the electron neutrino charged current interactions and the neutral current events. It is possible to have a dataset containing mostly $ν_e$CC events, by imposing appropriate selection cuts on the events. The $ν_μ$ CC and the neutral current events form the background to these events. This study uses the Monte Carlo generated neutrino events, to design the necessary selection …
In this paper, we present a study to measure the differences between the atmospheric neutrino and anti-neutrino oscillations in the Iron-Calorimeter detector at the India-based Neutrino Observatory experiment. Charged Current $ν_μ$ and $\overlineν_μ$ interactions with the detector under the influence of earth matter effect have been simulated for ten years of exposure. The observed $ν_μ$ and $\overlineν_μ$ events spectrum are separately binned into direction and energy bins, and a $χ^{2}$ is minimised with respect to each bin to extract the oscillation parameters for $ν_μ$ and $\overlineν_μ$ s…
Numerical qualification of an eco-friendly alternative gas mixture for avalanche mode operation of Resistive Plate Chambers is the soul of this work. To identify the gas mixture, a numerical model developed elsewhere by the authors has been first established by comparing the simulated figure of merits (efficiency and streamer probability) with the experimental data for the gas mixture used in INO-ICAL. Then it has been used to simulate the same properties of a gas mixture based on argon, carbon di-oxide and nitrogen, identified as potential replacement by studying its different properties. Eff…
The study has been carried out on the prospects of probing the sterile neutrino mixing with the magnetized Iron CALorimeter (ICAL) at the India-based Neutrino Observatory (INO), using atmospheric neutrinos as a source. The so-called 3~$+$~1 scenario is considered for active-sterile neutrino mixing and lead to projected exclusion curves in the sterile neutrino mass and mixing angle plane. The analysis is performed using the neutrino event generator NUANCE, modified for ICAL, and folded with the detector resolutions obtained by the INO collaboration from a full GEANT4 based detector simulation. …
The proposed ICAL experiment at INO aims to identify the neutrino mass hierarchy from observations of atmospheric neutrinos, and help improve the precision on the atmospheric neutrino mixing parameters. While the design of ICAL is primarily optimized to measure muon momentum, it is also capable of measuring the hadron energy in each event. Although the hadron energy is measured with relatively lower resolution, it nevertheless contains crucial information on the event, which may be extracted when taken concomitant with the muon data. We demonstrate that by adding the hadron energy information …
We report on a detailed simulation study of the hadron energy resolution as a function of the thickness of the absorber plates for the proposed Iron Calorimeter (ICAL) detector at the India-based Neutrino Observatory (INO). We compare the hadron resolutions obtained with absorber thicknesses in the range 1.5--8 cm for neutrino interactions in the energy range 2--15 GeV, which is relevant to hadron production in atmospheric neutrino interactions. We find that at lower energies, the thickness dependence of energy resolution is steeper than at higher energies, however there is a thickness-indepen…
Studies on Response Uniformity of RPC and Exploring Oscillation Dip and Valley, Non-Standard Interactions, and Earth's Core using Atmospheric Neutrinos at ICAL-INO detector
We study the sensitivity of the Iron Calorimeter (ICAL) at the India-Based Neutrino Observatory (INO) to Lorentz and CPT violation in the neutrino sector. Its ability to identify the charge of muons in addition to their direction and energy makes ICAL a useful tool in putting constraints on these fundamental symmetries. Using resolution, efficiencies, errors and uncertainties obtained from ICAL detector simulations, we determine sensitivities to $δ{b}_{31}$, which parametizes the violations in the muon neutrino sector. We carry out calculations for three generic cases representing mixing in th…
The proposed India-based Neutrino Observatory will host a 50 kton magnetized iron calorimeter (ICAL) with resistive plate chambers as its active detector element. Its primary focus is to study charged-current interactions of atmospheric muon neutrinos via the reconstruction of muons in the detector. We present the first study of the energy and direction reconstruction of the final state lepton and hadrons produced in charged current interactions of atmospheric electron neutrinos at ICAL and the sensitivity of these events to neutrino oscillation parameters $θ_{23}$ and $Δm_{32}^2$. However, th…
The India-based Neutrino Observatory (INO) will host a 50 kt magnetized iron calorimeter (ICAL@INO) for the study of atmospheric neutrinos. Using the detector resolutions and efficiencies obtained by the INO collaboration from a full-detector GEANT4-based simulation, we determine the reach of this experiment for the measurement of the atmospheric neutrino mixing parameters ($\sin^2 θ_{23}$ and $|Δm_{32}^2 |$). We also explore the sensitivity of this experiment to the deviation of $θ_{23}$ from maximal mixing, and its octant.
The recently approved India-based Neutrino Observatory will use the world's largest magnet to study atmospheric muon neutrinos. The 50 kiloton Iron Calorimeter consists of iron alternating with single-gap resistive plate chambers. A uniform magnetic field of $\sim$1.5 T is produced in the iron using toroidal-shaped copper coils. Muon neutrinos interact with the iron target to produce charged muons, which are detected by the resistive plate chambers, and tracked using orthogonal pick up strips. Timing information for each layer is used to discriminate between upward and downward traveling muons…
The neutral current non-standard interactions (NSI's) of neutrino with matter fermions while propagating through long distances inside the Earth matter can give rise to the extra matter potentials apart from the standard MSW potential due to the $W$-mediated interactions in matter. In this paper, we explore the impact of flavor violating neutral current NSI parameter $\varepsilon_{μτ}$ in the oscillation of atmospheric neutrino and antineutrino using the 50 kt magnetized ICAL detector at INO. We find that due to non-zero $\varepsilon_{μτ}$, $ν_μ\rightarrowν_μ$ and $\barν_μ\rightarrow\barν_μ$ t…
Flavor-dependent long-range leptonic forces mediated by the ultra-light and neutral bosons associated with gauged $L_e-L_μ$ or $L_e-L_τ$ symmetry constitute a minimal extension of the Standard Model. In presence of these new anomaly free abelian symmetries, the SM remains invariant and renormalizable, and can lead to interesting phenomenological consequences. For an example, the electrons inside the Sun can generate a flavor-dependent long-range potential at the Earth surface, which can enhance $ν_μ$ and $\barν_μ$ survival probabilities over a wide range of energies and baselines in atmospheri…
The upcoming 50 kt magnetized iron calorimeter (ICAL) detector at the India-based Neutrino Observatory (INO) is designed to study the atmospheric neutrinos and antineutrinos separately over a wide range of energies and path lengths. The primary focus of this experiment is to explore the Earth matter effects by observing the energy and zenith angle dependence of the atmospheric neutrinos in the multi-GeV range. This study will be crucial to address some of the outstanding issues in neutrino oscillation physics, including the fundamental issue of neutrino mass hierarchy. In this document, we pre…
The India-based Neutrino Observatory (INO) is a proposed underground facility located in India that will primarily house the magnetised Iron CALorimeter (ICAL) detector to study atmospheric neutrinos produced by interactions of cosmic rays with Earth's atmosphere. The physics goal is to to make precision measurements of the neutrino mixing and oscillation parameters through such a study. We present here the results from detailed simulations studies, as well as a status report on the project. In particular, we highlight the sensitivity of ICAL to the open issue of the neutrino mass ordering, wh…
The annihilation of Weakly Interactive Massive Particles (WIMP) in the centre of the sun could give rise to neutrino fluxes. We study the prospects of searching for these neutrinos at the upcoming Iron CALorimeter (ICAL) detector to be housed at the India-based Neutrino Observatory (INO). We perform ICAL simulations to obtain the detector efficiencies and resolutions in order to simulate muon events in ICAL due to neutrinos coming from annihilation of WIMP in the mass range $m_χ= (3-100)$ GeV. The atmospheric neutrinos pose a major background for these indirect detection studies and can be red…
The Iron Calorimeter (ICAL) detector at the India based Neutrino Observatory (INO) is planned to be set up in an underground cavern with a rock overburden of more than 1 km. This overburden reduces the cosmic muon flux by a factor of 10$^{6}$ with respect to that at sea level. In this paper, we examine the possibility of a 100 m shallow depth ICAL (SICAL) detector. The cosmic muons would have to be detected in a veto detector surrounding ICAL with an efficiency of 99.99 % in order to have the same level of muon background leaking undetected through the veto detector as at the 1 km depth underg…
In this paper, we study events without identifiable muon tracks in the Iron Calorimeter detector at the India-based Neutrino Observatory. Such events are dominated by high energy (E$_ν>$1 GeV) $ν_e$ charged current interactions, which have been studied only in a few experiments so far. The charged particles, produced in these neutrino interactions, give rise to a set of hits in the detector. We attempt to reconstruct the energy and the direction of the neutrino in such events. We study the energy distribution for a given pattern of hits of these events and find that the Landau distribution pro…
The Deep Underground Neutrino Experiment (DUNE) is a proposed next generation superbeam experiment at Fermilab. Its aims include measuring the unknown neutrino oscillation parameters -- the neutrino mass hierarchy, the octant of the mixing angle $θ_{23}$ and the CP violating phase $δ_{CP}$. The current and upcoming experiments T2K, NOvA and ICAL@INO will also be collecting data for the same measurements. In this paper, we explore the sensitivity reach of DUNE in combination with these other experiments. We evaluate the least exposure required by DUNE to determine the above three unknown parame…
The motivation for a cosmic muon veto (CMV) detector is to explore the possibility of locating the proposed large Iron Calorimeter (ICAL) detector at the India based Neutrino Observatory (INO) at a shallow depth. An initial effort in that direction, through the assembly and testing of a $\sim$ 1 m $\times$ 1 m $\times$ 0.3 m plastic scintillator based detector, is described. The plan for making a CMV detector for a smaller prototype mini-ICAL is also outlined.
Atmospheric neutrino experiments can show the "oscillation dip" feature in data, due to their sensitivity over a large $L/E$ range. In experiments that can distinguish between neutrinos and antineutrinos, like INO, oscillation dips can be observed in both these channels separately. We present the dip-identification algorithm employing a data-driven approach -- one that uses the asymmetry in the upward-going and downward-going events, binned in the reconstructed $L/E$ of muons -- to demonstrate the dip, which would confirm the oscillation hypothesis. We further propose, for the first time, the …
Atmospheric neutrino experiments can determine the neutrino mass hierarchy for any value of $δ_{CP}$. The Iron Calorimeter (ICAL) detector at the India-based Neutrino Observatory can distinguish between the charged current interactions of $ν_μ$ and $\barν_μ$ by determining the charge of the produced muon. Hence it is particularly well suited to determine the hierarchy. The hierarchy signature is more prominent in neutrinos with energy of a few GeV and with pathlength of a few thousand kilometers, $\textit{i.e.}$ neutrinos whose direction is not close to horizontal. We use adaptive neural netwo…
The magnetised 51 kton Iron Calorimeter (ICAL) detector proposed to be built at INO is designed with a focus on detecting 1-20 GeV muons. The magnetic field will enable the measurement of the momentum of the $μ^-$ and $μ^+$ generated from the charge current interactions of $ν_μ$ and $\barν_μ$ separately within iron in the detector, thus permitting the determination of the neutrino mass ordering/hierarchy, among other important goals of ICAL. Hence it is important to determine the magnetic field as accurately as possible. The mini-ICAL detector is an 85-ton prototype of ICAL, which is operation…
The India-based Neutrino Observatory (INO) is planning to build a magnetized iron calorimeter detector (ICAL) in which Resistive Plate Chambers (RPCs) will be the active detector elements. A study of the performance of RPCs, made using electrodes of various thicknesses, is pivotal in optimizing the design parameters of the ICAL RPCs. We fabricated RPCs with glasses of various thicknesses and studied their performance in the same environmental conditions. A study of detector efficiency, noise rate, time resolution and charge distribution is presented in this paper.
Exceptional Sensitivity to Neutrino Parameters with a Two Baseline Beta-Beam Set-up
We examine the reach of a Beta-beam experiment with two detectors at carefully chosen baselines for exploring neutrino mass parameters. Locating the source at CERN, the two detectors and baselines are: (a) a 50 kton iron calorimeter (ICAL) at a baseline of around 7150 km which is roughly the magic baseline, e.g., ICAL@INO, and (b) a 50 kton Totally Active Scintillator Detector at a distance of 730 km, e.g., at Gran Sasso. We choose 8B/8Li source ions with a boost factor γof 650 for the magic baseline while for the closer detector we consider 18Ne/6He ions with a range of Lorentz boosts. We fin…
The 50 \,kton\, INO-ICAL is a proposed underground high energy physics experiment at Theni, India ($9^{\circ}57'N$, $77^{\circ}16'E$) to study the neutrino oscillation parameters using atmospheric neutrinos. The Resistive Plate Chamber (RPC) has been chosen as the active detector element for the ICAL detector. An experimental setup consisting of 12 layers of glass RPCs of size 2\,m\,$\times$\,2\,m has been built at IICHEP, Madurai to study the long term stability and performance of RPCs which are produced on a large scale in Indian industry. In this paper, the studies on the performance of RPC…
We have analyzed the atmospheric neutrino data to study the octant of $θ_{23}$ and the precision of the oscillation parameters for a large Iron CALorimeter (ICAL) detector. The ICAL being a tracking detector has the ability to measure the energy and the direction of the muon with high resolution. From bending of the track in magnetic field it can also distinguish its charge. We have generated events by Nuance and then considered only the muons (directly measurable quantities) produced in charge current interactions in our analysis. This encounters the main problem of wide resolutions of energy…
The proposed 50 \,kton\, INO-ICAL experiment is an upcoming underground high energy physics experiment planned to be commissioned at Bodi hills near Theni, India ($9^{\circ}57'N$, $77^{\circ}16'E$) to study various properties of neutrino oscillations using atmospheric neutrinos produced by extensive air shower phenomenon. The resistive plate chamber has been chosen as the active detector element for the proposed INO-ICAL. An experimental setup consisting a stack of 12 layers of glass resistive plate chambers each with a size of $\sim$2\,m$\times$2\,m has been built at IICHEP, Madurai to study …
The India based Neutrino Observatory (INO) is a mega science project of India, which is going to use near about 30, 000 Resistive Plate Chambers (RPC) as active detector elements for the study of atmospheric neutrino oscillations. Each RPC detector will consist of two orthogonally placed readout strips panel for picking the signals generated in the gas chamber. The area of RPC detector in INO-ICAL (Iron Calorimeter) experiment will be 2m x 2m, therefore the dimension of readout strips panel will also be of 2m x 2m. To get undistorted signals pass through the readout strips panel to frontend el…
The India-based Neutrino Observatory (INO) is a project aimed at building a large underground laboratory to explore the Earth's mater effects on the atmospheric neutrinos in multi-GeV range. INO will host a 50 kton magnetized iron calorimeter detector (ICAL) in which Resistive Plate Chambers(RPCs) will be the active detector elements. In ICAL, 28,800 glass RPCs of 2 m $\times$ 2 m size will be operated in the avalanche mode. A small variation in the compositions of ionizing gaseous medium in the RPC affects its performance. Study of the charge distribution of the RPC at different gas compositi…
We propose a new approach to explore the neutral-current non-standard neutrino interactions (NSI) in atmospheric neutrino experiments using oscillation dips and valleys in reconstructed muon observables, at a detector like ICAL that can identify the muon charge. We focus on the flavor-changing NSI parameter $\varepsilon_{μτ}$, which has the maximum impact on the muon survival probability in these experiments. We show that non-zero $\varepsilon_{μτ}$ shifts the oscillation dip locations in $L/E$ distributions of the up/down event ratios of reconstructed $μ^-$ and $μ^+$ in opposite directions. W…
