Vibrational stability of a cryocooled horizontal double-crystal monochromator
(2016) In Journal of Synchrotron Radiation 23(Pt 5). p.1076-1081- Abstract
The vibrational stability of a horizontally deflecting double-crystal monochromator (HDCM) is investigated. Inherently a HDCM will preserve the vertical beam stability better than a `normal' vertical double-crystal monochromator as the vibrations of a HDCM will almost exclusively affect the horizontal stability. Here both the relative pitch vibration between the first and second crystal and the absolute pitch vibration of the second crystal are measured. All reported measurements are obtained under active cooling by means of flowing liquid nitrogen (LN2). It is found that it is favorable to circulate the LN2 at high pressures and low flow rates (up to 5.9 bar and down to 3 l min(-1) is tested) to attain low vibrations. An absolute pitch... (More)
The vibrational stability of a horizontally deflecting double-crystal monochromator (HDCM) is investigated. Inherently a HDCM will preserve the vertical beam stability better than a `normal' vertical double-crystal monochromator as the vibrations of a HDCM will almost exclusively affect the horizontal stability. Here both the relative pitch vibration between the first and second crystal and the absolute pitch vibration of the second crystal are measured. All reported measurements are obtained under active cooling by means of flowing liquid nitrogen (LN2). It is found that it is favorable to circulate the LN2 at high pressures and low flow rates (up to 5.9 bar and down to 3 l min(-1) is tested) to attain low vibrations. An absolute pitch stability of the second crystal of 18 nrad RMS, 2-2500 Hz, and a relative pitch stability between the two crystals of 25 nrad RMS, 1-2500 Hz, is obtained under cryocooling conditions that allow for 1516 W to be adsorbed by the LN2 before it vaporizes.
(Less)
- author
- Kristiansen, Paw ; Johansson, Ulf LU ; Ursby, Thomas LU and Jensen, Brian Norsk LU
- organization
- publishing date
- 2016-09-01
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Synchrotron radiation, X-ray optics
- in
- Journal of Synchrotron Radiation
- volume
- 23
- issue
- Pt 5
- pages
- 6 pages
- publisher
- International Union of Crystallography
- external identifiers
-
- pmid:27577758
- scopus:84984871026
- wos:000382299500003
- ISSN
- 1600-5775
- DOI
- 10.1107/S1600577516009243
- language
- English
- LU publication?
- yes
- id
- 12c620c1-1b81-4a58-9ad7-05df768ce5fc
- date added to LUP
- 2016-09-07 10:21:36
- date last changed
- 2024-09-20 22:32:09
@article{12c620c1-1b81-4a58-9ad7-05df768ce5fc, abstract = {{<p>The vibrational stability of a horizontally deflecting double-crystal monochromator (HDCM) is investigated. Inherently a HDCM will preserve the vertical beam stability better than a `normal' vertical double-crystal monochromator as the vibrations of a HDCM will almost exclusively affect the horizontal stability. Here both the relative pitch vibration between the first and second crystal and the absolute pitch vibration of the second crystal are measured. All reported measurements are obtained under active cooling by means of flowing liquid nitrogen (LN2). It is found that it is favorable to circulate the LN2 at high pressures and low flow rates (up to 5.9 bar and down to 3 l min(-1) is tested) to attain low vibrations. An absolute pitch stability of the second crystal of 18 nrad RMS, 2-2500 Hz, and a relative pitch stability between the two crystals of 25 nrad RMS, 1-2500 Hz, is obtained under cryocooling conditions that allow for 1516 W to be adsorbed by the LN2 before it vaporizes.</p>}}, author = {{Kristiansen, Paw and Johansson, Ulf and Ursby, Thomas and Jensen, Brian Norsk}}, issn = {{1600-5775}}, keywords = {{Synchrotron radiation; X-ray optics}}, language = {{eng}}, month = {{09}}, number = {{Pt 5}}, pages = {{1076--1081}}, publisher = {{International Union of Crystallography}}, series = {{Journal of Synchrotron Radiation}}, title = {{Vibrational stability of a cryocooled horizontal double-crystal monochromator}}, url = {{http://dx.doi.org/10.1107/S1600577516009243}}, doi = {{10.1107/S1600577516009243}}, volume = {{23}}, year = {{2016}}, }