Data Acquisition Architecture and Online Processing System for the HAWC gamma-ray observatory
HAWC collaboration, A. U. Abeysekara, R. Alfaro, C. Alvarez, J. D. Álvarez, R. Arceo, J. C. Arteaga-Velázquez, H. A. Ayala Solares, A. S. Barber, B. M. Baughman… 展开作者
HAWC collaboration, A. U. Abeysekara, R. Alfaro, C. Alvarez, J. D. Álvarez, R. Arceo, J. C. Arteaga-Velázquez, H. A. Ayala Solares, A. S. Barber, B. M. Baughman, N. Bautista-Elivar, J. Becerra Gonzalez, E. Belmont-Moreno, S. Y. BenZvi, D. Berley, M. Bonilla Rosales, J. Braun, R. A. Caballero-Lopez, K. S. Caballero-Mora, A. Carramiñana, M. Castillo, U. Cotti, J. Cotzomi, E. de la Fuente, C. De León, T. DeYoung, J. Diaz-Cruz, R. Diaz Hernandez, J. C. Díaz-Vélez, B. L. Dingus, M. A. DuVernois, R. W. Ellsworth, D. W. Fiorino, N. Fraija, A. Galindo, F. Garfias, M. M. González, J. A. Goodman, V. Grabski, M. Gussert, Z. Hampel-Arias, J. P. Harding, C. M. Hui, P. Hüntemeyer, A. Imran, A. Iriarte, P. Karn, D. Kieda, G. J. Kunde, A. Lara, R. J. Lauer, W. H. Lee, D. Lennarz, H. León Vargas, E. C. Linares, J. T. Linnemann, M. Longo Proper, R. Luna-García, K. Malone, A. Marinelli, S. S. Marinelli, O. Martinez, J. Martínez-Castro, H. Martínez-Huerta, J. A. J. Matthews, J. McEnery, E. Mendoza Torres, P. Miranda-Romagnoli, E. Moreno, M. Mostafá, L. Nellen, M. Newbold, R. Noriega-Papaqui, T. Oceguera-Becerra, B. Patricelli, R. Pelayo, E. G. Pérez-Pérez, J. Pretz, C. Rivière, D. Rosa-González, E. Ruiz-Velasco, J. Ryan, H. Salazar, F. Salesa Greus, F. E. Sanchez, A. Sandoval, M. Schneider, S. Silich, G. Sinni, A. J. Smith, K. Sparks Woodle, R. W. Springer, I. Taboada, P. A. Toale, K. Tollefson, I. Torres, T. N. Ukwatta, L. Villaseñor, T. Weisgarber, S. Westerhoff, I. G. Wisher, J. Wood, T. Yapici, G. B. Yodh, P. W. Younk, D. Zaborov, A. Zepeda, H. Zhou
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14 pages, 3 figures, submitted to Nucl. Instrum. Meth. A
The High Altitude Water Cherenkov observatory (HAWC) is an air shower array devised for TeV gamma-ray astronomy. HAWC is located at an altitude of 4100 m a.s.l. in Sierra Negra, Mexico. HAWC consists of 300 Water Cherenkov Detectors, each instrumented with 4 photomultiplier tubes (PMTs). HAWC re-uses the Front-End Boards from the Milagro experiment to receive the PMT signals. These boards are used in combination with Time to Digital Converters (TDCs) to record the time and the amount of light in each PMT hit (light flash). A set of VME TDC modules (128 channels each) is operated in a continuous (dead time free) mode. The TDCs are read out via the VME bus by Single-Board Computers (SBCs), which in turn are connected to a gigabit Ethernet network. The complete system produces ~ 500 MB/s of raw data. A high-throughput data processing system has been designed and built to enable real-time data analysis. The system relies on off-the-shelf hardware components, an open-source software technology for data transfers (ZeroMQ) and a custom software framework for data analysis (AERIE). Multiple trigger and reconstruction algorithms can be combined and run on blocks of data in a parallel fashion, producing a set of output data streams which can be analyzed in real time with minimal latency (< 5 s). This paper provides an overview of the hardware set-up and an in-depth description of the software design, covering both the TDC data acquisition system and the real-time data processing system. The performance of these systems is also discussed.
The HAWC (High Altitude Water Cerenkov) gamma ray observatory observes muons with nearly-horizontal trajectories corresponding to zenith angles greater than $80^{0}$. HAWC is located at an altitude of 4100 meters a.s.l. (70 deg. atmospheric depth of 2400 g/cm$^{2}$) on the extinct volcano, Sierra Negra in Mexico. In this poster, we summarize the CORSIKA and GEANT4 as well as toy-model based simulations performed to determine the effective area of HAWC to muons from high zenith angle cosmic ray primaries. We are developing an updated GEANT4 based detector response simulation that includes a mod…
The HAWC collaboration has recently completed the construction of a gamma-ray observatory at an altitude of 4100 meters on the slope of the Sierra Negra volcano in the state of Puebla, Mexico. In order to achieve an optimal angular resolution, energy reconstruction, and cosmic-ray background suppression for the air showers observed by HAWC, it is crucial to obtain good timing and charge calibrations of the photosensors in the detector. The HAWC calibration is based on a laser system which is able to deliver short light pulses to all the tanks in the array. The light intensity can range over 7 …
The High Altitude Water Cherenkov (HAWC) high-energy γ-ray observatory was completed in march 2015 in central Mexico. The detector, consisting of 300 water tanks, is currently being upgraded to improve its performance at Multi-TeV energies, with a sparse array of small water Cherenkov tanks. It will extend the instrumental area by a factor of 4, and enhance the sensitivity at the highest energies. In this contribution, the current status of the observatory is presented, as well as the coming upgrade. The electronics and the readout system for the new sparse array of small water tanks are also …
The High Altitude Water Cherenkov (HAWC) gamma-ray observatory has been fully operational since March 2015. To improve its sensitivity at the highest energies, it is being upgraded with an additional sparse array called outrigger array. We will discuss in this contribution, the different outrigger array components, and the simulation results to optimize it.
The HAWC gamma ray observatory, to be constructed at Sierra Negra, Puebla in Mexico, is a large array of water Cherenkov detectors sited at an elevation of 4100 m, which has been optimized for gamma/hadron discrimination of the primary cosmic rays in the TeV energy range. It is based on the Milagro experience, but the design has been changed from a water pond to individual water tanks. In order to validate the design with large water tanks a prototype array has been constructed near the HAWC site with 3 of the largest commercial rotomolded plastic tanks available in Mexico. They have been inst…
The High Altitude Water Cherenkov (HAWC) observatory is an air-shower array located in Mexico. It is sensitive to the highest energy photons we detect at the Earth, reaching energies of several tens of TeV. The observatory was completed more than one year ago and we are presenting in this contribution the first results about its performance. We also show the results of the first-year survey, the first flaring events detected by the observatory, its sensitivity to extended sources and the plans for the upgrade that is currently taking place.
The HAWC (High Altitude Water Cherenkov) gamma ray observatory is able to observe muons with nearly horizontal trajectories. HAWC is located at an altitude of 4100 meters a.s.l. on the Sierra Negra volcano in Mexico. The HAWC detector is composed of 300 water tanks, each 7.3 m in diameter and 4.5 m tall, densely packed over a physical area of 22,000 m$^{2}$. Previous and current experiments have observed high zenith angle (near horizontal) muons at or near sea level. HAWC operates as a hodoscope able to observe multi-TeV muons at zenith angles greater than 75 degrees. This is the first experim…
The detection of ultra-high energy neutrinos, with energies in the PeV range or above, is a topic of great interest in modern astroparticle physics. The importance comes from the fact that these neutrinos point back to the most energetic particle accelerators in the Universe, and provide information about their underlying acceleration mechanisms. Atmospheric neutrinos are a background for these challenging measurements, but their rate is expected to be negligible above $\approx$ 1 PeV. In this work we describe the feasibility to study ultra-high energy neutrinos based on the Earth-skimming tec…
The High-Altitude Water Cherenkov (HAWC) Observatory is used for detecting TeV gamma rays. HAWC is operating at 4,100 meters above level sea on the slope of the Sierra Negra Volcano in the State of Puebla, Mexico, and consists of an array of 300 water Cherenkov detectors (WCDs) covering an area of 22,000 $m^2$. Each WCD is equipped with four photomultiplier tubes (PMTs) to detect Cherenkov emission in the water from secondary particles of extensive air-shower (EAS) that are produced in the interactions of primary particles (gamma rays or charged cosmic rays) in the atmosphere. HAWC is able to …
A wide range of data formats and proprietary software have traditionally been used in gamma-ray astronomy, usually developed for a single specific mission or experiment. However, in recent years there has been an increasing effort towards making astronomical data open and easily accessible. Within the gamma-ray community this has translated to the creation of a common data format across different gamma-ray observatories: the "gamma-astro-data-format" (GADF). Based on a similar premise, open-source analysis packages, such as Gammapy, are being developed and aim to provide a single, robust tool …
The High Altitude Water Cherenkov (HAWC) Observatory is an air shower array located near the volcano Sierra Negra in Mexico. The observatory has a scaler system sensitive to low energy cosmic rays (the geomagnetic cutoff for the site is 8 GV) suitable for conducting studies of solar or heliospheric transients such as Ground Level Enhancements (GLEs) and Forbush decreases. In this work we present the simulation of the HAWC response to these phenomena. We computed HAWC effective areas for different array configurations (different selection of photomultiplier tubes per detector) relevant for Forb…
There are currently over 160 known gamma-ray pulsars. While most of them are detected only from space, at least two are now seen also from the ground. MAGIC and VERITAS have measured the gamma ray pulsed emission of the Crab pulsar up to hundreds of GeV and more recently MAGIC has reported emission at $\sim2$ TeV. Furthermore, in the Southern Hemisphere, H.E.S.S. has detected the Vela pulsar above 30 GeV. In addition, non-pulsed TeV emission coincident with pulsars has been detected by many groups, including the Milagro Collaboration. These GeV-TeV observations open the possibility of searchin…
The High Altitude Water Cherenkov (HAWC) gamma-ray observatory consists of 300 water Cherenkov detectors and has been fully operational since March 2015 in central Mexico. It detects cosmic- and gamma-ray showers in the TeV energy range. For multi-TeV energies, the shower reconstruction and hence the performance of the detector is affected by the partial containment of the showers within the array. To improve the sensitivity at the highest energies, HAWC is being upgraded with an outrigger array. It consists of 350 comparably much smaller water Cherenkov detectors, sparsely distributed around …
The High-Altitude Water Cherenkov (HAWC) observatory in central Mexico is currently the world's only synoptic survey instrument for gamma rays above 1 TeV. Because there is significant interest in covering the full TeV sky with a survey instrument, we have examined options for a Southern Hemisphere extension to HAWC. In addition to providing all-sky coverage of TeV sources, a southern site could complement existing surveys of the densest part of the Galactic Plane, provide continuous monitoring of Galactic and extragalactic transient sources in both Hemispheres, and simplify the analysis of sp…
The close location of the HAWC observatory to the largest volcano in Mexico allows to perform a search for neutrino-induced horizontal muon and tau charged leptons. The section of the volcano located at the horizon reaches values of slant depth larger than 8 km of rock, making it an excellent shield for the cosmic ray horizontal background. We report the search method and background suppression technique developed for the detection of Earth-skimming neutrinos with HAWC, as well as a model that describes the remaining background produced by scattered muons. We show that by increasing the detect…
The High-Altitude Water Cherenkov (HAWC) Observatory was completed and began full opera- tion on March 20, 2015. The detector consists of an array of 300 water tanks, each containing 200 ktons of purified water and instrumented with 4 PMTs. Located at an elevation of 4100m a.s.l. near the Sierra Negra volcano in central Mexico, HAWC has a threshold for gamma-ray detection well below 1 TeV and a sensitivity to TeV-scale gamma-ray sources an order of magnitude better than previous air-shower arrays. The detector operates 24 hours/day and observes the overhead sky (2 sr), making it an ideal surve…
The High-Altitude Water Cherenkov (HAWC) Observatory is a ground based air-shower array deployed on the slopes of Volcan Sierra Negra in the state of Puebla, Mexico. While HAWC is optimized for the detection of gamma-ray induced air-showers, the background flux of hadronic cosmic-rays is four orders of magnitude greater, making background rejection paramount for gamma-ray observations. On average, gamma-ray and cosmic-ray showers are characterized by different topologies at ground level. We will present a method to identify the primary particle type in an air-shower that uses the spatial relat…
The High-Altitude Water Cherenkov experiment (HAWC) observatory is located 4100 meters above sea level. HAWC is able to detect secondary particles from extensive air showers (EAS) initiated in the interaction of a primary particle (either a gamma or a charged cosmic ray) with the upper atmosphere. Because an overwhelming majority of EAS events are triggered by cosmic rays, background noise suppression plays an important role in the data analysis process of the HAWC observatory. Currently, HAWC uses cuts on two parameters (whose values depend on the spatial distribution and luminosity of an eve…
The High Altitude Water Cherenkov (HAWC) observatory is a TeV gamma-ray and cosmic-ray detector currently under construction at an altitude of 4100 m close to volcano Sierra Negra in the state of Puebla, Mexico. The HAWC observatory is an extensive air-shower array comprised of 300 optically-isolated water Cherenkov detectors (WCDs). Each WCD contains $\sim$200,000 liters of filtered water and four upward-facing photomultiplier tubes. In Fall 2014, when the HAWC observatory will reach an area of 22,000 m$^{2}$, the sensitivity will be 15 times higher than its predecessor Milagro. Since Septemb…
In this contribution, the first results of HAWC, searching for VHE gamma-ray emission from gamma-ray bursts (GRBs) reported by $\mathit{Swift}$, are presented. The HAWC gamma-ray observatory is operating in central Mexico at an altitude of 4,100 m above sea level. With an instantaneous field of view of approximately 2 sr and over 95% duty cycle (up time fraction), HAWC is an ideal detector to perform ground-based gamma-ray observations of GRBs. Though optimised for TeV observations, HAWC has significant sensitivity to short transients of energies as small as 50 GeV. The analysis method used fo…
The High Altitude Water Cherenkov (HAWC) gamma-ray observatory observes atmospheric showers produced by incident gamma rays and cosmic rays with energy from 300 GeV to more than 100 TeV. A crucial phase in analyzing gamma-ray sources using ground-based gamma-ray detectors like HAWC is to identify the showers produced by gamma rays or hadrons. The HAWC observatory records roughly 25,000 events per second, with hadrons representing the vast majority ($>99.9\%$) of these events. The standard gamma/hadron separation technique in HAWC uses a simple rectangular cut involving only two parameters. Thi…
The Stratospheric Observatory for Infrared Astronomy (SOFIA) is a Boeing 747SP aircraft modified to accommodate a 2.7 meter gyro-stabilized telescope, which is mainly focused to studying the Universe at infrared wavelengths. As part of the Strategic Director's Discretionary Time (S-DDT) program, SOFIA performs observations of relevant science cases and immediately offers science-ready data products to the astronomical community. We present the first data release of the S-DDT program on far-infrared imaging polarimetric observations of 30 Doradus using the High-resolution Airborne Wideband Came…
The High Altitude Water Cherenkov (HAWC) gamma-ray observatory detects cosmic- and gamma-ray initiated air showers in the TeV energy range using 300 water Cherenkov detectors (WCDs). To improve its sensitivity at the highest energies, HAWC has been upgraded with a sparse array of 345 small WCDs (outrigger array) around the HAWC main array. The outrigger array increases the instrumented area of HAWC by a factor of 4 and has started taking data since August 2018. A new gamma-ray reconstruction method has been developed to improve the reconstruction of the air showers which combines the data of m…
VAMOS was a prototype detector built in 2011 at an altitude of 4100m a.s.l. in the state of Puebla, Mexico. The aim of VAMOS was to finalize the design, construction techniques and data acquisition system of the HAWC observatory. HAWC is an air-shower array currently under construction at the same site of VAMOS with the purpose to study the TeV sky. The VAMOS setup included six water Cherenkov detectors and two different data acquisition systems. It was in operation between October 2011 and May 2012 with an average live time of 30%. Besides the scientific verification purposes, the eight month…
The High-Altitude Water Cherenkov Gamma Ray Observatory (HAWC) is under construction 4100 meters above sea level at Sierra Negra, Mexico. We describe the design and cabling of the detector, the characterization of the photomultipliers, and the timing calibration system. We also outline a next-generation detector based on the water Cherenkov technique.
The High Altitude Water Cherenkov (HAWC) is a wide field-of-view gamma-ray observatory sensitive to gamma-rays in the 300 GeV - 100 TeV energy range, located in Mexico at an altitude of 4,100 m above sea level. The detector consists of 300 Water Cherenkov Detectors with a volume of 200,000 l each, having a footprint of 22,000 $m^2$, a duty cycle of >95% and a field of view (FoV) of 2sr. In this work we present a general data quality inspection of HAWC data for the years between 2014 and 2017 and also for two specific data periods selected on the base that GRB 150416A and GRB 160301A detected b…
High-energy cosmic rays that hit the Earth can be used to study large-scale atmospheric perturbations. After a first interaction in the upper parts of the atmosphere, cosmic rays produce a shower of particles that sample the atmosphere down to the detector level. The HAWC (High-Altitude Water Cherenkov) cosmic-ray observatory in Central Mexico at 4,100 m elevation detects air shower particles continuously with 300 water Cherenkov detectors with an active area of 12,500 m$^{2}$. On January 15th, 2022, HAWC detected the passage of the pressure wave created by the explosion of the Hunga volcano i…
This paper summarizes a presentation given on the occasion of the inauguration of the High Altitude Water Cherenkov (HAWC) Gamma-ray Observatory in Puebla, Mexico in March 2015. The inauguration of a new facility for the study of astrophysical gamma-rays provides an excellent opportunity to review the technical evolution and the scientific achievements of VERITAS (the Very Energetic Radiation Imaging Telescope Array System) since its own inauguration in 2007. HAWC and VERITAS are separated by only 14 degrees in longitude, and so can view much of the same sky at the same time. In combination wi…
The High Altitude Water Cherenkov (HAWC) observatory is a very high energy gamma-ray detector located in Mexico. In late 2018, the HAWC collaboration completed a major upgrade consisting of the addition of a sparse outrigger array of 345 small water Cherenkov detectors (WCDs) surrounding the 300 WCDs of the main array and extending the instrumented area by a factor of 4. It provides an improved reconstruction of the showers whose core and footprint are not well contained in the array and increases the effective area in the range of a few TeV to beyond 100 TeV. This improvement in sensitivity w…
The High Altitude Water Cherenkov (HAWC) gamma-ray observatory is located at an altitude of 4100 meters in Sierra Negra, Puebla, Mexico. HAWC is an air shower array of 300 water Cherenkov detectors (WCD's), each with 4 photomultiplier tubes (PMTs). Because the observatory is sensitive to air showers produced by cosmic rays and gamma rays, one of the main tasks in the analysis of gamma-ray sources is gamma/hadron separation for the suppression of the cosmic-ray background. Currently, HAWC uses a method called compactness for the separation. This method divides the data into 10 bins that depend …
Background showers triggered by hadrons represent over 99.9% of all particles arriving at ground-based gamma-ray observatories. An important stage in the data analysis of these observatories, therefore, is the removal of hadron-triggered showers. Currently, the High-Altitude Water Cherenkov (HAWC) gamma-ray observatory employs an algorithm based on a single cut in two variables, unlike other ground-based gamma-ray observatories (e.g. H.E.S.S., VERITAS), which employ a large number of variables to separate the primary particles. In this work, we explore machine learning techniques (Boosted Deci…
The High altitude Water Cherenkov (HAWC) Observatory has been completed and began full operation in early 2015. Located at an elevation of 4,100 m near the Sierra Negra volcano in the state of Puebla, Mexico, HAWC consists of 300 water tanks instrumented with 4 PMTs each. The array is optimized for detecting air showers produced by gamma rays with energies between 100 GeV and 100 TeV and can also be used to measure charged cosmic rays. A wide instantaneous field of view of ~2 steradians and a duty cycle >95% allow HAWC to survey two-thirds of the sky every day. These unique capabilities make i…
The High Altitude Water Cherenkov (HAWC) Observatory continuously observes gamma-rays between 100 GeV to 100 TeV in an instantaneous field of view of about 2 steradians above the array. The large amount of raw data, the importance of small number statistics, the large dynamic range of gamma-ray signals in time (1 - $10^8$ sec) and angular extent (0.1 - 100 degrees), and the growing need to directly compare results from different observatories pose some special challenges for the analysis of HAWC data. To address these needs, we have designed and implemented a modular analysis framework based o…
The FemtoDAQ is a low-cost two channel data acquisition system which we have used to investigate the signal characteristics of silicon photomultipliers (SiPMs) coupled to fast scintillators. The FemtoDAQ system can also be used to instrument low cost moderate performance passive detectors, and is suitable for use in harsh environments (e.g., high altitude). The FemtoDAQ is being used as a SiPM test bench for the High Altitude Water Cherenkov (HAWC) Observatory, a TeV gamma ray detector located 4100 m above sea level. Planned upgrades to the HAWC array can benefit greatly from SiPMs, a robust, …
The High Altitude Water Cherenkov (HAWC) gamma-ray observatory is a ground-based air shower array designed to detect Cherenkov light produced in water by secondary particles from atmospheric air showers. In order to improve the sensitivity at the highest energies, especially for the shower cores falling outside the main array, 345 smaller Water Cherenkov Detectors (WCDs) were installed around the main array, the outrigger array. This extension increased the instrumented area of HAWC by a factor of four. With the increased size of the array, and the ability to detect shower particles further aw…
The High Altitude Water Cherenkov (HAWC) high-energy gamma-ray observatory has recently been completed on the slopes of the Sierra Negra volcano in central Mexico. HAWC consists of 300 Water Cherenkov Detectors, each containing 180 m$^3$ of ultra-purified water, that cover a total surface area of 20,000 m$^2$. It detects and reconstructs cosmic- and gamma-ray showers in the energy range of 100 GeV to 100 TeV. The HAWC trigger for the highest energy gammas reaches an effective area of 10$^5$ m$^2$ but many of them are poorly reconstructed because the shower core falls outside the array. An upgr…
The HAWC Gamma Ray observatory consists of 300 water Cherenkov detectors (WCD) instrumented with four photo multipliers tubes (PMT) per WCD. HAWC is located between two of the highest mountains in Mexico. The high altitude (4100 m asl), the relatively short distance to the Gulf of Mexico (~100 km), the large detecting area (22 000 m$^2$) and its high sensitivity, make HAWC a good instrument to explore the acceleration of particles due to the electric fields existing inside storm clouds. In particular, the scaler system of HAWC records the output of each one of the 1200 PMTs as well as the 2, 3…
Studying gamma-ray emission by Galactic objects is key to understanding the origins and acceleration mechanisms of Galactic cosmic ray electrons and hadrons. The HAWC observatory provides an unprecedented view of the gamma-ray sky at TeV energies and is particularly suited for the study of Galactic objects. However, the interpretation of the measured data poses several challenges. The high density of sources and source candidates can cause source confusion and make it harder to disentangle the origin of the emission. The relatively low angular resolution of HAWC, compared to instruments in opt…
The Fermi bubbles are structures observed in gamma rays at GeV energies, emanating from the central region of our galaxy and extending up to 8.5 kpc above and below the galactic plane. While initial studies showed a flat brightness across the entire structure, more recent work found a brightening at the base. We perform a template-based search for TeV signals from the northern Fermi bubble and just from the base of it in data from the High Altitude Water Cherenkov (HAWC) gamma-ray observatory. We employ a profile likelihood approach to calculate the significance and flux from the search region…
The High-Altitude Water-Cherenkov (HAWC) experiment is a TeV $γ$-ray observatory located \unit[4100]{m} above sea level on the Sierra Negra mountain in Puebla, Mexico. The detector consists of 300 water-filled tanks, each instrumented with 4 photomultiplier tubes that utilize the water-Cherenkov technique to detect atmospheric air showers produced by cosmic $γ$ rays. Construction of HAWC was completed in March of 2015. The experiment's wide instantaneous field of view (\unit[2]{sr}) and high duty cycle (> 95\%) make it a powerful survey instrument sensitive to pulsars, supernova remnants, and …
The Southern Wide-field Gamma-ray Observatory (SWGO) Collaboration is currently engaged in design and prototyping work towards the realisation of this future gamma-ray facility. SWGO will complement CTA and the existing ground-particle based-detectors of the Northern Hemisphere (HAWC and LHAASO) with a very wide field and high duty cycle view of the southern sky. Here I summarise the status of the project and plans for the future, including expectations for sensitivity and science targets as well as the status of the site search and technological developments.
The variation in atmospheric pressure is due to changes in mass of the air column above, which in turn resembles the density variation of atmosphere and will affect the decay of secondary particles of cosmic rays. The ground based cosmic ray detectors observe pressure dependent variation in their flux. The High Altitude Water Cherenkov (HAWC) gamma ray observatory is a great detector of secondary particles because of its high altitude, high uptime, and large area (including total photo-cathode area), which makes the HAWC scaler system an ideal instrument for solar modulation studies. Although,…
Strong electric fields in thunderclouds have long been known to accelerate secondary charged particles. We investigate this effect using three years (2015-2017) of data from the scalar system of the High Altitude Water Cherenkov (HAWC) observatory, which is an air shower array deployed 4100 m a.s.l. in central Mexico. The experimental site is frequently affected by strong thunderstorms, and the detector's high altitude, large area, and high sensitivity to cosmic-ray air showers make it ideal for investigating particle acceleration due to the electric fields present inside the thunder storm clo…
The HAWC observatory reconstructs atmospheric showers induced by very high-energy primary cosmic- or gamma-rays. Cosmic-rays with hadronic nature are several orders of magnitude more frequent than primary gammas and therefore it is necessary to perform the best gamma-hadron discrimination for each event to be able to survey the gamma-ray sky. Single vertical muons cause very characteristic signals in the 300 HAWC detectors. Particularly, those events that produce signals in the four PMTs of a tank corresponding to muons traversing the tank in the central region. In such cases exist the correla…
Innovative Web Tool for Remote Data Acquisition and Analysis: Customized for SKA Low frequency Beamforming Test Bed LPDA Array at Gauribidanur Radio Observatory
The very-high-energy gamma-ray sky can be surveyed on a daily basis by particle-detector arrays at high (mountain) elevation. In the northern hemisphere the survey recently conducted by the HAWC gamma-ray observatory significantly enriched our knowledge about TeV gamma-ray sources. In this contribution, we will present an overview on the effort to realise a next-generation gamma-ray survey observatory in the southern hemisphere. We will discuss the unique science case for this observatory and how it will be embedded in the multi-messenger and multi-wavelength census of the non-thermal universe…
A scientific instrument comprised of a global network of millions of independent, connected, remote devices presents unique data acquisition challenges. We describe the software design of a mobile application which collects data from smartphone cameras without overburdening the phone's CPU or battery. The deployed software automatically calibrates to heterogeneous hardware targets to improve the quality and manage the rate of data transfer, and connects to a cloud-based data acquisition system which can manage and refine the operation of the network.
The scientific potential of a wide field-of-view, and very-high duty cycle, ground-based gamma-ray detector has been demonstrated by the current generation of instruments, such as HAWC and ARGO, and will be further extended in the Northern Hemisphere by LHAASO. Nevertheless, no such instrument exists in the Southern Hemisphere yet, where a great potential lies uncovered for the mapping of Galactic large scale emission as well as providing access to the full sky for transient and variable multi-wavelength and multi-messenger phenomena. Access to the Galactic Centre and complementarity with the …
