{"product_id":"shelyak-el0037","title":"Shelyak Thorium-Argon Lamp for Shelyak Spectrographs","description":"\u003cul class=\"DAV-feature-list\"\u003e\n\u003cli\u003eElement Composition: Thorium-Argon (ThAr)\u003c\/li\u003e\n\u003cli\u003eLamp Type: Hollow Cathode Lamp (HCL)\u003c\/li\u003e\n\u003cli\u003ePrimary Application: High-resolution spectrograph calibration\u003c\/li\u003e\n\u003cli\u003eDesigned For: Shelyak eShel and Whoppshel spectrographs\u003c\/li\u003e\n\u003cli\u003eOutput: Dense, well-defined emission lines across the spectrum\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- more --\u003e\n\u003cul class=\"tabs\"\u003e\n\u003cli class=\"active\"\u003eDescription\u003c\/li\u003e\n\u003cli\u003eFAQ\u003c\/li\u003e\n\n\u003cli\u003eDownloads\u003c\/li\u003e\n\u003cli\u003eWarranty\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cul class=\"tabs-content\"\u003e\n\u003cli class=\"active\"\u003e\n\u003cdiv\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section-center\"\u003e\n\u003ch2\u003eThorium-Argon Lamp for Shelyak Spectrographs\u003c\/h2\u003e\n\u003cp\u003eThis Thorium-Argon (ThAr) hollow cathode lamp is the reference calibration source for Shelyak's high-resolution eShel and Whoppshel spectrographs. It is engineered to produce a rich spectrum of sharp, distinct emission lines, providing the necessary data points for an exceptionally precise wavelength calibration across the entire visible spectrum. This component is the replacement bulb for the eShel calibration module, enabling you to maintain the scientific accuracy of your spectroscopic observations.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eA High-Density Emission Line Source for Echelle Calibration\u003c\/h3\u003e\n\u003cp\u003eThe accuracy of any spectrograph is fundamentally limited by the quality of its wavelength calibration. Thorium-Argon is the standard for professional instruments because it provides thousands of well-characterized emission lines. For an echelle spectrograph, which spreads light into multiple overlapping orders, this density of lines is critical for correctly identifying wavelengths and achieving sub-Angstrom accuracy.\u003c\/p\u003e\n\u003cp\u003eUsing this ThAr lamp, you can create a master calibration frame that maps the unique optical path of your system. This allows the instrument software to precisely assign a wavelength to every pixel on the sensor, transforming raw data into a scientifically valid spectrum for radial velocity studies, stellar classification, and chemical composition analysis.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-bg-light\"\u003e\n\u003cdiv class=\"DAV-section\"\u003e\n\u003ch3\u003eReplacement Bulb: Essential System Requirements\u003c\/h3\u003e\n\u003cp\u003eThis product is the Thorium-Argon hollow cathode lamp bulb only. It is intended as a direct replacement for a depleted or damaged lamp within an existing Shelyak eShel calibration unit or for custom-built spectroscopic systems. It is not a standalone device and requires specific external hardware to operate.\u003c\/p\u003e\n\u003cp\u003eTo power the lamp and excite the gas to produce its characteristic spectrum, you must have a compatible high-voltage power supply and the appropriate interface cable. These components are part of the complete eShel calibration module but are not included with this replacement bulb. Please ensure your existing power supply and connections are in working order before purchasing.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat is this Thorium-Argon lamp used for in astronomy?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe \u003cstrong\u003eThorium-Argon lamp\u003c\/strong\u003e is a calibration light source. It produces a very dense and well-known pattern of emission lines. By taking a spectrum of the lamp, astronomers can create a precise map of wavelengths onto the camera's sensor pixels, which is essential for analyzing the spectra of stars and other celestial objects accurately.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eIs this a complete, ready-to-use calibration unit?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eNo. This is the \u003cstrong\u003ereplacement bulb only\u003c\/strong\u003e. It is a component that requires a separate high-voltage power supply and an interface cable to operate. It is designed to be installed into a device like the Shelyak eShel calibration module.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eHow do I use the Thorium-Argon lamp to calibrate my eShel spectrograph?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe lamp is installed in the eShel calibration module, which feeds the light into the spectrograph via a fiber optic cable. You will take a dedicated calibration exposure of the lamp's spectrum. Using software like Demetra, this known ThAr spectrum is compared to your image to create a precise wavelength solution for all subsequent scientific observations.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhy is Thorium-Argon the standard for the Shelyak Thorium-Argon lamp?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThorium-Argon is the professional standard for high-resolution spectroscopy for two main reasons. First, it produces an extremely high density of emission lines across the visible spectrum. Second, these lines are very sharp and their wavelengths are known to an extremely high degree of accuracy, making the \u003cstrong\u003eShelyak Thorium-Argon lamp\u003c\/strong\u003e an ideal reference source.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat telescope is this Thorium-Argon lamp and eShel system best suited for?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eThe eShel system, for which this \u003cstrong\u003eThorium-Argon lamp\u003c\/strong\u003e is a component, is typically used with Schmidt-Cassegrain or Ritchey-Chrétien telescopes in the 8\" to 14\" aperture range. The system is optimized for telescopes with focal ratios around f\/10, though it can be adapted to others. The goal is to achieve sufficient light grasp to record high-resolution spectra of moderately bright stars.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion\"\u003e\n\u003ch3 class=\"DAV-accordion-Q\"\u003eWhat do I need to power this Thorium-Argon lamp?\u003c\/h3\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"DAV-accordion-A\"\u003e\n\u003cp\u003eYou will need a specific \u003cstrong\u003ehigh-voltage power supply\u003c\/strong\u003e designed for hollow cathode lamps, as well as the correct interface cable. These items are not included with the bulb. This lamp is intended as a direct replacement for the one included in the complete Shelyak eShel calibration module, which already contains the necessary power electronics.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/li\u003e\n\n\u003cli\u003e\n\u003cul class=\"DAV-grid\"\u003e\n\u003cli class=\"DAV-grid-item\"\u003e\u003ca href=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Shelyak_eShel_Manual.pdf\" target=\"_blank\"\u003e\u003csvg class=\"DAV-img-box\" viewbox=\"0 0 512 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"\u003e\u003cpath d=\"M0 64C0 28.7 28.7 0 64 0L224 0l0 128c0 17.7 14.3 32 32 32l128 0 0 144-208 0c-35.3 0-64 28.7-64 64l0 144-48 0c-35.3 0-64-28.7-64-64L0 64zm384 64l-128 0L256 0 384 128zM176 352l32 0c30.9 0 56 25.1 56 56s-25.1 56-56 56l-16 0 0 32c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-48 0-80c0-8.8 7.2-16 16-16zm32 80c13.3 0 24-10.7 24-24s-10.7-24-24-24l-16 0 0 48 16 0zm96-80l32 0c26.5 0 48 21.5 48 48l0 64c0 26.5-21.5 48-48 48l-32 0c-8.8 0-16-7.2-16-16l0-128c0-8.8 7.2-16 16-16zm32 128c8.8 0 16-7.2 16-16l0-64c0-8.8-7.2-16-16-16l-16 0 0 96 16 0zm80-112c0-8.8 7.2-16 16-16l48 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 32 32 0c8.8 0 16 7.2 16 16s-7.2 16-16 16l-32 0 0 48c0 8.8-7.2 16-16 16s-16-7.2-16-16l0-64 0-64z\" fill=\"#0047a7\"\u003e\u003c\/path\u003e\u003c\/svg\u003e\n\u003cdiv\u003e\n\u003cp class=\"DAV-item-title\"\u003eShelyak eShel Manual\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/davidastro.com\/pages\/shelyak-warranty-policy\" rel=\"noopener\" target=\"_blank\"\u003eShelyak 1-Year Warranty\u003c\/a\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Shelyak","offers":[{"title":"Default Title","offer_id":52943028715805,"sku":"SHK-EL0037","price":1060.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0753\/5280\/1565\/files\/Shelyak-Thorium-Argon-lamp-1_be0533dc-5749-40e8-a2c9-3a3d8e3f86fd.jpg?v=1789615859","url":"https:\/\/davidastro.com\/en-us\/products\/shelyak-el0037","provider":"David Astro","version":"1.0","type":"link"}