arXiv subjects

K. C. Ravindran

Publications and source records attributed to K. C. Ravindran.

10 recordsLinked to original sources

arXiv2026

Design and Implementation of a UDP-Based Command Interface for the INO ICAL Experiment

Efficient command interface is a critical requirement for experiments employing a large number of front-end DAQ modules and control servers. In the context of the INOICAL (India-based Neutrino Observatory Iron Calorimeter) experiment, this involves 28,800 Resistive Plate Chamber(RPC), charged particle detectors. The acquisition and control of these detectors are facilitated through Front End data acquisition modules known as RPC-DAQs. These modules consists of Ethernet interfaces for data and command connectivity to a server. Each module acts as a network node with a unique IP address. The collective group of hundreds of modules is controlled by a common server over a Local Area Network (LAN). UDP (User Datagram Protocol) is the most commonly used networking protocol which supports Multicast as well as Unicast, can be easily adapted to INO ICAL Experiment. A server can send commands to group of DAQs or any particular DAQ. But UDP may have the problem of packet loss and reliability. To mitigate these issues, this paper suggests a simpler approach that modifies the UDP protocol by implementing a handshaking scheme and checksum, similar to those found in more reliable protocols like TCP. The proposed solution optimizes the use of UDP as a reliable command interface in the INO ICAL experiment, ensuring seamless data acquisition and control. Also, this paper shows the performance study of the custom hybrid UDP Command Interface in the prototype ICAL experiment called Mini Iron Calorimeter (Mini ICAL) which houses 20 units of RPCs and electronics. This work not only addresses the challenges of the INO ICAL experiment but also underscores the adaptability and robustness of the proposed protocol for usage in mini-ICAL and beyond.

physics.ins-det↗

arXiv2025

TCP/IP based Remote Firmware Upgradation for INO ICAL RPC-DAQ Modules

The INO ICAL (India-based Neutrino Observatory Iron Calorimeter) experiment is an upcoming mega-science project currently in the developmental stages. This initiative employs over 28,800 Resistive Plate Chambers (RPC) based charged particle detectors used for tracking muon events. Each of these detectors incorporates an FPGA-based Digital Front End known as RPC-DAQ, with the primary objective of measuring the position and timing of particle interactions within the respective RPCs. The firmware embedded in the RPC-DAQ FPGA is designed to support this logic. The ICAL experiment is a 50-kiloton iron structure arranged in a stacked geometry where the RPCs along with their associated electronics are positioned between these iron plates. Reprogramming individual or groups of RPC-DAQs proves to be a challenging and time consuming task. To address the complexity of upgrading firmware for these typically inaccessible RPC-DAQs this paper introduces an innovative approach that utilizes the existing Ethernet interface, employed for command transmission and data acquisition to upload firmware. A customized handshaking architecture has been designed using the TCP protocol for this experiment. The firmware binary file is segmented into TCP packets and transmitted over Ethernet. The soft-core processor instantiated in the RPC-DAQ FPGA receives these firmware packets overwriting the existing firmware in the flash memory. Upon rebooting the RPC-DAQ configures the new firmware on the FPGA. The entire firmware upgrade process takes around 13 seconds to configure 10 RPC-DAQs. This paper explains the details of the architecture governing the firmware upgrade process and providing a comprehensive understanding of its mechanics.

physics.ins-det↗

arXiv2025

NIOS II Soft-Core Processor and Ethernet Controller Solution for RPC-DAQ in INO ICAL

This paper introduces a high-performance Soft-Core Processor based data acquisition system designed for handling Resistive Plate Chambers (RPCs). The DAQ consist of FPGA-based hardware equipped with Soft-Core Processor and embedded hardwired Ethernet controllers named RPC-DAQ, offering a versatile and fast network-enabled data acquisition solution. A soft processor, NIOS, is instantiated within an Intel Cyclone IV FPGA, overseeing control, communication, and data transfer with remote processing units. These integrated RPC-DAQ units, in substantial numbers, connect to a limited set of high-end processing units via LAN switches. This paper provides a detailed account of the software implementation scheme for the NIOS processor in the RPC-DAQ system. A remarkable 28,800 RPC-DAQ units will be deployed in proximity to the RPCs, serving the proposed INO-ICAL experiment in Theni-Madurai, Tamil Nadu. The network-enabled RPC-DAQ units controlled by the soft processor offloads FPGA tasks including event data acquisition, periodic health monitoring of RPCs, command interfaces, high voltage control, and data transfer to back-end data concentrators. Communication and data transfer are executed efficiently via TCP and UDP protocols over a 100 Mbps Ethernet interface. This system provides innovative solutions to improve data acquisition and control in large-scale scientific experiments.

physics.ins-det↗

arXiv2023

Improving Time and Position Resolution of RPC detectors using Time Over Threshold Information

INO-ICAL is a proposed underground particle physics experiment to study the neutrino oscillation parameters by detecting neutrinos produced in the atmospheric air showers. Iron CALorimeter (ICAL) is to have 151 layers of iron stacked vertically, with active detector elements in between the iron layers. The iron layers will be magnetized to enable the measurement of momentum and charge of the $μ^-$ (or $μ^+$) produced by $ν_μ$ (or $\barν_μ$) interactions. Resistive Plate Chambers (RPCs) have been chosen as the active detector elements due to their large area coverage, uncompromised sensitivity, consistent performance for decades, as well as cost effectiveness. The major factors that decide the physics potential of the ICAL experiment are efficiency, position resolution and time resolution of the large area RPCs. A prototype detector called miniICAL (with 11 iron layers) was commissioned to understand the engineering challenges in building the large scale magnet and its ancillary systems, and also to study the performance of the RPC detectors and readout electronics developed by the INO collaboration. As part of the performance study of the RPC detectors, an attempt is made to improve the position and time resolution of them. Even a small improvement in the position and time resolution will help to improve the measurements of momentum and directionality of the neutrinos in ICAL. The Time-over-Threshold (ToT) of the RPC pulses (signals) is recorded by the readout electronics. ToT is a measure of the pulse width and consequently the amplitude. This information is used to improve the time and position resolution of the RPCs and consequently INO physics potential.

physics.ins-det↗

arXiv2023

Design, fabrication and large scale qualification of cosmic muon veto scintillator detectors

The INO collaboration is designing a cosmic muon veto detector (CMVD) to cover the mini-ICAL detector which is operational at the IICHEP transit campus, Madurai in South India. The aim of the CMVD is to study the feasibility of building an experiment to record rare events at a shallow depth of around 100 m, and use plastic scintillators to veto atmospheric muons from those produced by the rare interactions within the target mass of the detector. The efficiency of such a veto detector should be better than 99.99% and false positive rate of less than $10^{-5}$. The CMVD is being built using extruded plastic scintillator (EPS) strips to detect and tag atmospheric muons. More than 700 EPS strips are required to build the CMVD. Two EPS strips are pasted together to make a di-counter (DC) and wavelength shifting fibres are embedded inside the EPS strips to trap the scintillation light generated by a passing cosmic ray muon and transmit it as secondary photons to the Silicon Photo-Multipliers (SiPMs) mounted at the two ends of the DCs. Since the efficiency requirement of the veto detector is rather high, it is imperative to thoroughly test each and every component used for building the CMVD. A cosmic ray muon telescope has been setup using the DCs to qualify all the DCs that will be fabricated. In this paper we will discuss the details of the design and fabrication of the DCs, and the cosmic muon setup and the electronics used for their testing and the test results.

physics.ins-det↗

arXiv2022

Optimisation of Operating High Voltage of the large area Resistive Plate Chamber for ICAL experiment

The Resistive Plate Chamber is a widely used detector in high energy physics. The operating potential of this chamber is determined by the optimisation of the efficiency and noise rate of the device. This optimisation is based on the assumption that the performance of the device over the whole surface area is uniform. The INO-ICAL experiment is going to use $\sim$ 30000 RPC of size $\sim$2\,m$\times$2\,m. All the RPC will have to pass a minimum quality assurance criteria, but may not be able to maintain a good uniformity over the whole surface area, particularly for the whole running period of about twenty years. This paper describes the choice of the optimum operating HV for an RPC of non-uniform response.

physics.ins-det↗

arXiv2020

Study of Particle Multiplicity of Cosmic Ray Events using 2m$\times$2m Resistive Plate Chamber Stack at IICHEP-Madurai

An experimental setup consisting of 12 layers of glass Resistive Plate Chambers (RPCs) of size 2\,m\,$\times$\,2\,m has been built at IICHEP-Madurai (\ang{9;56;14.5}\,N \ang{78;00;47.9}\,E, on the surface) to study the long term performance and stability of RPCs produced on large scale in Indian industry. This setup has been collecting data triggered by the passage of charged particles. The measurement of the multiplicity of charged particles due to cosmic ray interactions are presented here. Finally, the results are compared with different hadronic models of the CORSIKA simulation.

astro-ph.HE↗

arXiv2020

Measurement of azimuthal dependent muon flux by 2\,m\,$\times$\,2\,m RPC stack at IICHEP-Madurai

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$2\,m has been built at IICHEP, Madurai to study the performance and long-term stability of the resistive plate chambers(RPCs) commercially produced in large quantities by the Indian industries as well as its electronics for the front-end and subsequent signal processing. In this study, the azimuthal dependence of muon flux at various zenith angles at Madurai (9$^{\circ}$56'N, 78$^{\circ}$00'E and at an altitude of 160\,m above mean sea level) has been presented along with the comparison of Monte Carlo from CORSIKA and HONDA predictions.

hep-ex↗

arXiv2019

Leak Test of Resistive Plate Chamber Gap by Monitoring Absolute Pressure

The India-based Neutrino Observatory Project (INO) is a proposed underground high energy physics experiment at Theni, India to study the neutrino oscillation parameters using atmospheric neutrinos. The 50 kton magnetised INO-ICAL detector will require approximately 30,000 of 2m$\times$2m Resistive Plate Chambers (RPC) as sensitive detectors and proposed to operate for about 20 years. For success of the experiment, each of the RPCs has to function without showing any significant aging during the period of operation. Hence, various tests including a proper leak test are performed during and after production. The methods of leak rate calculation using conventional manometer are valid only when both the volume of the test subject and ambient pressure are kept constant. But both these quantities for a RPC gas gap depend widely on the ambient pressure and temperature. A proper quantitative estimation of the leak rate cannot be acquired from such pressure measurements. By monitoring the absolute pressures, both outside and inside of an RPC, along with the temperature, its leakage rate can be estimated. During the test period, the supporting button spacers inside an RPC may get detached due to manufacturing defect. This effect also needs to be detected.

physics.ins-det↗

arXiv2017

Measurement of Cosmic Muon angular distribution and vertical integrated flux by 2m$\times$2m RPC stack at IICHEP-Madurai

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 RPCs are presented along with the angular distribution of muons at Madurai ($9^{\circ}56'N,78^{\circ}00'E$ and Altitude $\approx$\,160\,m from sea level).

physics.ins-det↗