Atmospheric Dispersion Measurement at Hanle Site

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Bestha, Manjunath, Thirupathi, Sivarani, Unni, Athira, M, Parvathy, Divakar, Devika
Natura: Preprint
Pubblicazione: 2025
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866914102537879552
author Bestha, Manjunath
Thirupathi, Sivarani
Unni, Athira
M, Parvathy
Divakar, Devika
author_facet Bestha, Manjunath
Thirupathi, Sivarani
Unni, Athira
M, Parvathy
Divakar, Devika
contents Atmospheric dispersion introduces wavelength-dependent effects that significantly impact ground-based observations, particularly in slit- and fibre-fed spectroscopic studies. These effects reduce the signal entering the spectrograph and introduce systematic errors in radial velocity measurements. To address this challenge, atmospheric dispersion correctors are utilised. However, many existing designs of these correctors, which are based on theoretical models, often lack practical validation and consistency. The forthcoming National Large Optical Telescope (NLOT) will be installed at Hanle, a site known for its favourable astronomical sky conditions. Thus, the design of an effective dispersion corrector for the instruments on the NLOT, specifically one that compensates for the measured dispersion, is crucial. For the first time, we have directly measured atmospheric dispersion at the Hanle site using the Himalayan Faint Object Spectrograph mounted on the Himalayan Chandra Telescope. In this study, we present our methodology, the dispersion measurements obtained within the 400 to 700 nm wavelength range, and a comparison with modelled dispersion values.
format Preprint
id arxiv_https___arxiv_org_abs_2509_17300
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Atmospheric Dispersion Measurement at Hanle Site
Bestha, Manjunath
Thirupathi, Sivarani
Unni, Athira
M, Parvathy
Divakar, Devika
Instrumentation and Methods for Astrophysics
Earth and Planetary Astrophysics
Atmospheric dispersion introduces wavelength-dependent effects that significantly impact ground-based observations, particularly in slit- and fibre-fed spectroscopic studies. These effects reduce the signal entering the spectrograph and introduce systematic errors in radial velocity measurements. To address this challenge, atmospheric dispersion correctors are utilised. However, many existing designs of these correctors, which are based on theoretical models, often lack practical validation and consistency. The forthcoming National Large Optical Telescope (NLOT) will be installed at Hanle, a site known for its favourable astronomical sky conditions. Thus, the design of an effective dispersion corrector for the instruments on the NLOT, specifically one that compensates for the measured dispersion, is crucial. For the first time, we have directly measured atmospheric dispersion at the Hanle site using the Himalayan Faint Object Spectrograph mounted on the Himalayan Chandra Telescope. In this study, we present our methodology, the dispersion measurements obtained within the 400 to 700 nm wavelength range, and a comparison with modelled dispersion values.
title Atmospheric Dispersion Measurement at Hanle Site
topic Instrumentation and Methods for Astrophysics
Earth and Planetary Astrophysics
url https://arxiv.org/abs/2509.17300