Commissioning and first result of undulator based atomic, molecular, and optical sciences (AMOS) beamline at Indus-2 synchrotron radiation source

Param Jeet Singh; Tamaghna Maitra; A K Das; A K Yadav; Ravi Kumar; Ankur Agarwal; Ashutosh Dvivedi; K K Gorai; A Shastri; D Bhattacharyya; D V Udupa

doi:10.1063/5.0238362

Commissioning and first result of undulator based atomic, molecular, and optical sciences (AMOS) beamline at Indus-2 synchrotron radiation source

Rev Sci Instrum. 2024 Dec 1;95(12):123307. doi: 10.1063/5.0238362.

Authors

Param Jeet Singh^{1

2}, Tamaghna Maitra³, A K Das¹, A K Yadav¹, Ravi Kumar¹, Ankur Agarwal³, Ashutosh Dvivedi³, K K Gorai³, A Shastri^{1

2}, D Bhattacharyya^{1

2}, D V Udupa^{1

2}

Affiliations

¹ Atomic and Molecular Physics Division, Bhabha Atomic Research Centre, Mumbai 400094, India.
² Homi Bhabha National Institute, Bhabha Atomic Research Centre, Mumbai 400094, India.
³ Beamline Development and X-ray Application Section, Bhabha Atomic Research Centre, Mumbai 400094, India.

PMID: 39724326
DOI: 10.1063/5.0238362

Abstract

We present a comprehensive overview of the commissioning process and initial results of a synchrotron beamline dedicated to atomic, molecular, and optical sciences at the BL-5 undulator port of the Indus-2 synchrotron facility, Raja Ramanna Center for Advanced Technology, Indore, India. The beamline delivers a photon flux of ∼1012 photons/s with high resolving power (∼10 000) over an energy range of 6-800 eV, making it suitable for high-resolution spectroscopy in atomic, molecular, and optical science. The energy tunability from vacuum ultraviolet to soft x-ray (6-800 eV) is achieved through a varied line spacing plane grating monochromator with four gratings: very low energy (VLEG), low energy (LEG), medium energy (MEG), and high energy (HEG). These gratings cover ranges of 6-18, 15-45, 42-126, and 90-800 eV, respectively. A differential pumping system allows windowless transmission of VUV and soft x-ray photons for gas-phase spectroscopic experiments. The beamline also includes an x-ray absorption spectroscopy (XAS) station for solid samples. To demonstrate efficiency, a spectrum was recorded using all four gratings in the 6-300 eV energy range. Standard spectra of Xe and O2 verified the resolution, achieving a resolving power of 7740 with the VLEG, consistent with design specifications. XAS spectra of Cu M, C, and O K-edges were also obtained using MEG and HEG. Details on vacuum level, grating operation, and the first commissioning experiments are presented.