The Cherenkov Telescope Array (CTA) is the next-generation gamma-ray observatory that is expected to reach one order of magnitude better sensitivity than that of current telescope arrays. The Large-Sized Telescopes (LSTs) have an essential role in extending the energy range down to 20 GeV. The prototype LST (LST-1) proposed for CTA was built in La Palma, the northern site of CTA, in 2018. LST-1 is currently in its commissioning phase and moving towards scientific observations. The LST-1 camera consists of 1855 photomultiplier tubes (PMTs) which are sensitive to Cherenkov light. PMT signals are recorded as waveforms sampled at 1 GHz rate with Domino Ring Sampler version 4 (DRS4) chips. Fast sampling is essential to achieve a low energy threshold by minimizing the integration of background light from the night sky. Absolute charge calibration can be performed by the so-called F-factor method, which allows calibration constants to be monitored even during observations. A calibration pipeline of the camera readout has been developed as part of the LST analysis chain. The pipeline performs DRS4 pedestal and timing corrections, as well as the extraction and calibration of charge and time of pulses for subsequent higher-level analysis. The performance of each calibration step is examined, and especially charge and time resolution of the camera readout are evaluated and compared to CTA requirements. We report on the current status of the calibration pipeline, including the performance of each step through to signal reconstruction, and the consistency with Monte Carlo simulations.
The Large-Sized Telescopes (LSTs) of Cherenkov Telescope Array (CTA) are designed for gamma-ray studies focusing on low energy threshold, high flux sensitivity, rapid telescope repositioning speed and a large field of view. Once the CTA array is complete, the LSTs will be dominating the CTA performance between 20 GeV and 150 GeV. During most of the CTA Observatory construction phase, however, the LSTs will be dominating the array performance until several TeVs. In this presentation we report on the status of the LST-1 telescope inaugurated in La Palma, Canary islands, Spain in 2018. We show th…
The Cherenkov Telescope Array (CTA) will be the next generation gamma-ray observatory, which will consist of three kinds of telescopes of different sizes. Among those, the Large Size Telescope (LST) will be the most sensitive in the low energy range starting from 20 GeV. The prototype LST (LST-1) proposed for CTA was inaugurated in October 2018 in the northern hemisphere site, La Palma (Spain), and is currently in its commissioning phase. MAGIC is a system of two gamma-ray Cherenkov telescopes of the current generation, located approximately 100 m away from LST-1, that have been operating in s…
The prototype of the Large-Sized Telescope (LST) of the Cherenkov Telescope Array (CTA) is presently going through its commissioning phase. A total of four LSTs, among others, will operate together at Observatorio del Roque de Los Muchachos, which will host the CTA North site. A computing center endowed with 1760 cores and several petabytes disk space is installed onsite. It is used to acquire, process, and analyze the data produced, at a rate of 3~TB/hour during operation. The LST On-site Analysis LSTOSA is a set of scripts written in Python which connects the different steps of lstchain, the…
The Cherenkov Telescope Array (CTA) is the next generation of ground-based gamma-ray observatory. The observatory will consist of two arrays, one located in the southern hemisphere (Paranal,Chile) and the other in the northern hemisphere (Canary Island, Spain), covering the whole sky in the range of observation. More than 100 telescopes are planned to be in operation for as long as 30 years, which motivated the development of a continuous condition monitoring of the individual telescopes. The main goal of the monitoring is to detect degradation and failures before critical damages occur. Two a…
The Cherenkov Telescope Array (CTA) will consist of two arrays of Imaging Atmospheric Cherenkov Telescopes (IACTs) at the northern and southern hemispheres. CTA will feature IACTs with mirrors of three different sizes optimized to cover different energy ranges. The proposed sub-arrays of four Large Size Telescopes (LST) at CTA-North and CTA-South target the lowest energy range between around 20 GeV and 100 GeV. Thanks to their low weight of around 110 tons the LSTs can move by 180 deg in azimuth in 20 seconds for Gamma Ray Burst (GRB) follow-up. An LST has a tessellated parabolic mirror of 23 …
The Cherenkov Telescope Array (CTA) is the next-generation gamma-ray observatory currently under construction. It will improve over the current generation of imaging atmospheric Cherenkov telescopes (IACTs) by a factor of five to ten in sensitivity and it will be able to observe the whole sky from a combination of two sites: a northern site in La Palma, Spain, and a southern one in Paranal, Chile. CTA will also be the first open gamma-ray observatory. Accordingly, the data analysis pipeline is developed as open-source software. The event reconstruction pipeline accepts raw data of the telescop…
The Cherenkov Telescope Array (CTA) will be the world's largest and most sensitive ground-based gamma-ray observatory in the energy range from a few tens of GeV to tens of TeV. The LST-1 prototype, currently in its commissioning phase, is the first of the four largest CTA telescopes, that will be built in the northern site of CTA in La Palma, Canary Islands, Spain. In this contribution, we present a full-image reconstruction method using a modified InceptionV3 deep convolutional neural network applied on non-parametrized shower images. We evaluate the performance of optimized networks on Monte…
Ground-based gamma-ray astronomy aims at reconstructing the energy and direction of gamma rays from the extensive air showers they initiate in the atmosphere. Imaging Atmospheric Cherenkov Telescopes (IACT) collect the Cherenkov light induced by secondary charged particles in extensive air showers (EAS), creating an image of the shower in a camera positioned in the focal plane of optical systems. This image is used to evaluate the type, energy and arrival direction of the primary particle that initiated the shower. This contribution shows the results of a novel reconstruction method based on l…
The atmospheric monitoring devices for the planned calibration system of the Cherenkov Telescope Array (CTA) are undergoing intensive development, prototyping and testing. The All-Sky Cameras, the Sun/Moon Photometers and the FRAM telescopes have been gradually deployed at the future CTA sites with the primary goal of site characterization, simultaneously allowing the assessment of their operational reliability in realistic environmental conditions. All three devices have shown the ability to work smoothly in both the extreme dryness and the large temperature variations of the southern site as…
A Silicon Photomultiplier (SiPM)-based photodetector is being built to demonstrate its feasibility for an alternative silicon-based camera design for the Large Size Telescope (LST) of the Cherenkov Telescope Array. It has been designed to match the size of the standard Photomultiplier Tube (PMT) cluster unit and to be compatible with mechanics, electronics and focal plane optics of the first LST camera. Here, we describe the overall SiPM cluster design along with the main differences with respect to the currently used PMT cluster unit. The fast electronics of the SiPM pixel and its layout are …
The Cherenkov Telescope Array (CTA) is the next generation very high energy gamma-ray observatory covering the 20 GeV - 300 TeV energy range with unprecedented sensitivity, angular and energy resolution. With a site in each hemisphere, CTA will provide full-sky coverage. Four Large Size Telescopes (LSTs) in each site will be dedicated to the lowest energy range (20 GeV - 200 GeV). The first LST prototype has been installed at the CTA Northern site (Canary Island of La Palma, Spain) in October 2018 and it had been since then in commissioning phase. LST1 is located at about 100 m from MAGIC, a s…
切伦科夫望远镜阵列（CTA）天文台将部署在两个半球的两个地点。这两个地点都将配备四个大尺寸望远镜（LST），这对于实现CTA在20-200 GeV能量范围内的科学目标至关重要。每个LST都配备了一个直径为23米的主镶嵌镜盘，由主要由碳纤维增强塑料管和铝接头制成的结构支撑。这种解决方案保证了重量轻（约100吨），这对于在20秒内快速重新定位到天空中的任何位置至关重要。该相机由1855个光电倍增管组成，并嵌入了控制、读出和触发电子器件。详细设计现已完成，第一架LST的生产正在进行中，该架LST将作为其余七架的原型。第一个LST安装在加那利群岛拉帕尔马岛（西班牙）的Roque de los Muchachos天文台于2016年7月开始。在本文中，我们将概述为满足设计要求而采用的技术解决方案，介绍元件原型设计的结果，并描述安装和操作计划。
The first Large-Sized Telescope (LST-1) proposed for the forthcoming Cherenkov Telescope Array (CTA) has started to operate in 2019 in La Palma. The large structure of LST-1 - with a 23 m mirror dish diameter - imposes a strict control of its deformations that could affect the pointing accuracy and its overall performance. According to CTA specifications that are conceived to resolve e.g. the fine structure of galactic sources, the LST post-calibration pointing accuracy should be better than 14 arcseconds. To fulfill this requirement, the telescope pointing precision is monitored with two dedi…
The Cherenkov Telescope Array (CTA) is the next-generation ground-based observatory for very-high energy gamma-ray astronomy. CTA will have unparalleled sensitivity and angular resolution and will detect gamma-ray sources nearly 100 times faster than current arrays, enabling valuable multiwavelength and multimessenger observations. The Schwarzschild-Couder Telescope (SCT) is a candidate for the Medium-Sized telescope in CTA. A prototype SCT (pSCT) has been constructed at the Fred Lawrence Whipple Observatory in Arizona USA. Its camera is currently partially instrumented with 1600 pixels (2.7 d…
Status of the Cherenkov Telescope Array's Large Size Telescopes
切伦科夫望远镜阵列（CTA）天文台将部署在两个半球的两个地点。这两个地点都将配备四个大尺寸望远镜（LST），这对于实现CTA在20-200 GeV能量范围内的科学目标至关重要。每个LST都配备了一个直径为23米的主镶嵌镜盘，由主要由碳纤维增强塑料管和铝接头制成的结构支撑。这种解决方案保证了重量轻（约100吨），这对于在20秒内快速重新定位到天空中的任何位置至关重要。该相机由1855个光电倍增管组成，并嵌入了控制、读出和触发电子器件。详细设计现已完成，第一架LST的生产正在顺利进行，该架LST将作为其余七架的原型。2016年，第一个LST将安装在西班牙拉帕尔马加那利岛的Roque de los Muchachos天文台。在这次演讲中，我们将概述为满足设计要求而采用的技术解决方案，介绍元件原型设计的结果，并描述安装和操作计划。
The Large-Sized Telescope (LST) prototype of the future Cherenkov Telescope Array (CTA) is located at the Northern site of CTA, on the Canary Island of La Palma. It is designed to provide optimal performance in the lowest part of the energy range covered by CTA, observing gamma rays down to energies of tens of GeV. The LST prototype started performing astronomical observations in November 2019 during the commissioning of the telescope and it has been taking data since then. In this contribution, we will present the tuning of the characteristics of the telescope in the Monte Carlo (MC) simulati…
The upcoming Cherenkov Telescope Array (CTA) ground-based gamma-ray observatory will open up our view of the very high energy Universe, offering an improvement in sensitivity of 5-10 times that of previous experiments. NectarCAM is one of the proposed cameras for the Medium-Sized Telescopes (MST) which have been designed to cover the core energy range of CTA, from 100 GeV to 10 TeV. The final camera will be capable of GHz sampling and provide a field of view of 8 degrees with its 265 modules of 7 photomultiplier each (for a total of 1855 pixels). In order to validate the performance of NectarC…
切伦科夫望远镜阵列（CTA）将是在甚高能伽马射线（20 GeV - 300 TeV）范围内运行的最大的地面天文台。它将以位于两个地点（北半球和南半球）的100多个望远镜为基础。南部CTA阵列的能量覆盖范围将扩展到数百TeV，这要归功于70台小型望远镜（SST），其主镜直径约为4米，视场约为9度。建议CTA SST阵列的首批前兆之一将由九台应科院望远镜代表。他们的原型，名为应科院SST-2 M，安装在意大利。它目前正在完成整体调试，然后进入科学验证阶段，将观测明亮的TeV源，如蟹状星云，Mrk 421和Mrk 501，并将原型性能与Monte Carlo预测进行交叉检查。应科院的望远镜采用双镜光学设计，以史瓦西-库德（SC）配置为基础。焦平面相机是弯曲的，以适应SC设计的理想处方和传感器是小尺寸的硅光电倍增器读出的快速前端电子。安装在意大利的望远镜原型由意大利国家天体物理研究所（INAF）开发，采用端到端的方法，包括从整个硬件和软件系统的设计、建造和实施到最终科学产品的所有方面。系统的所有部件均设计为符合CTA要求。目前，INAF正在与圣保罗大学（巴西）、西北大学（南非）和意大利国家核物理研究所（Italian National Institute for Nuclear Physics）合作，为CTA南部站点安装第一台应科院望远镜。
The landscape of ground-based gamma-ray astronomy is drastically changing with the perspective of the Cherenkov Telescope Array (CTA) composed of more than 100 Cherenkov telescopes. For the first time in this energy domain, CTA will be operated as an observatory open to the astronomy community. In this context, a structured high level data model is being developed to describe a CTA observation. The data model includes different classes of metadata on the project definition, the configuration of the instrument, the ambient conditions, the data acquisition and the data processing. This last part…
The Cherenkov Telescope Array (CTA) is a future ground-based gamma-ray observatory that will provide unprecedented sensitivity and angular resolution for the detection of gamma rays with energies above a few tens of GeV. In comparison to existing instruments (like H.E.S.S., MAGIC, and VERITAS) the sensitivity will be improved by installing two extended arrays of telescopes in the northern and southern hemisphere, respectively. A large number of planned telescopes (>100 in total) motivates the application of predictive maintenance techniques to the individual telescopes. A constant and automati…
The Cherenkov Telescope Array (CTA) is the next generation ground based observatory for gamma ray astronomy at very high energies. Employing more than 100 Imaging Atmospheric Cherenkov Telescopes in the northern and southern hemispheres, it was designed to reach unprecedented sensitivity and energy resolution. Understanding and correcting for systematic biases on the absolute energy scale and instrument response functions will be a crucial issue for the performance of CTA. The LUPM group and the Spanish/Italian/Slovenian collaboration are currently building two Raman LIDAR prototypes for the o…
The ASTRI Project: prototype status and future plans for a Cherenkov dual-mirror small-telescope array
应科院（Astrofisica con Specchi a Tecnologia Replicante Italiana）是意大利教育、大学和研究部的旗舰项目。在这一框架内，国家航空航天研究所目前正在开发CTA小型望远镜的宽视场（直径9.6度）端对端原型，专门用于研究从几分之一TeV到几十TeV的能量范围，并计划于2014年开始数据采集。为了获得紧凑的光学结构，切伦科夫望远镜将首次采用双反射镜Schwarzschild-Couder光学设计。第二个具有挑战性但创新的技术解决方案包括基于硅光电倍增器的模块化焦面相机，逻辑像素尺寸为6.2mm x 6.2mm。在这里，我们描述了该项目的当前状态，预期的性能，其可能的演变方面的SST微型阵列。这个CTA-SST的前身由几个SST组成，并与CTA国际合作伙伴合作开发，不仅可以仔细研究应科院采用的技术解决方案，还可以解决几个详细讨论的科学测试案例。
Once completed, the Cherenkov Telescope Array (CTA) will be able to map the gamma-ray sky in a wide energy range from several tens of GeV to some hundreds of TeV and will be more sensitive than previous experiments by an order of magnitude. It opens up the opportunity to observe transient phenomena like gamma-ray bursts (GRBs) and flaring active galactic nuclei (AGN). In order to successfully trigger multi-wavelength observations of transients, CTA has to be able to alert other observatories as quickly as possible. Multi-wavelength observations are essential for gaining insights into the proce…
The Cherenkov Telescope Array (CTA) will use three telescope sizes to efficiently detect cosmic gamma rays in the energy range from several tens of GeV to hundreds of TeV. The Small-Sized Telescopes (SSTs) will form the largest section of the array, covering an area of many square kilometres on the CTA southern site in Paranal, Chile. Up to 70 SSTs will be implemented by an international consortium of institutes and teams as an in-kind contribution to the CTA Observatory. The SSTs will provide unprecedented sensitivity to gamma rays above 1 TeV and the highest angular resolution of any instrum…
The Cherenkov Telescope Array (CTA) project, led by an international collaboration of institutes, aims to create the world's largest next generation observatory for Very High Energy (VHE) gamma-ray astronomy. It will be devoted to observations in a wide band of energy, from a few tens of GeV to a few hundreds of TeV with Large, Medium and Small-sized telescopes. The Small-Size Telescopes (SSTs) are dedicated to the highest energy range above a few TeV and up to 300 TeV. GCT is an imaging atmospheric Cherenkov telescope (IACT) proposed for the subarray of about 70 SSTs to be installed on the So…
