Table 3. Comparison of ROBL-II with other dedicated radionuclide beamlines.
| ROBL-II | INE-KARA | ACT-KARA | Mars-SOLEIL | microXAS-SLS | |
|---|---|---|---|---|---|
| Reference | This paper | (Rothe et al., 2012 ▸) | (Zimina et al., 2016 ▸, 2017 ▸) | (Llorens et al., 2014 ▸; Sitaud et al., 2012 ▸) | (Borca et al., 2009 ▸) |
| Source | SBM (0.6 T) on 6 GeV ring at 200 mA | BM (1.6 T) on 2.5 GeV ring at 200 mA | Superconducting 2.5 T wiggler on 2.5 GeV ring at 200 mA | BM (1.7 T) on 2.75 GeV ring at 500 mA | Minigap in-vacuum undulator |
| Photon flux | 6 × 1012 ph/s at 20 keV and 200 mA | 2 × 1010 ph/s at 18 keV | 1011 ph/s at 20 keV and 100 mA | 1 × 1012 ph/s at 12 keV and 430 mA | 3 × 1012 ph/s at 12 keV |
| Mirror 1 | VCM† (Si, Rh, Pt) at 2.5 mrad | VCM (Rh) at 2.7 mrad) | VCM (Si, Rh, Pt), mirror-less | VCM (Si, Pt) | Horizontally deflecting toroid (Rh)‡ |
| DCM | Si(111), Si(111)30°, Si(311) multilayer | Si(111), Si(311), Ge(422), InSb(111) | Si(111), Si(311) | Si(111) and Si(220) on sagittal bender for horizontal focusing | Si(111), Si(311), Ge(111) |
| Mirror 2 | Double-toroid (Rh, Pt), VFM§ (Si) | Toroid (Rh) | Double-toroid (Si, Rh), VFM (Ir), mirror-less | VFM (Si, Pt) | Elliptical Kirkpatrick–Baez (KB) (Rh) |
| Energy range (keV) | 3.5–35 | 2.1–25 | 3.4–55 | 3.5–35 | 4–23 |
| Spot size on sample (h × v) (µm) | 21 × 69 (focused) 10000 × 2000 (unfocused) | 500 × 500 | 1000 × 1000 (focused) | 300 × 300 15 × 15 (with additional KB optics) | 1.0 × 1.0 with 1011 ph/s dynamic focusing |
| Maximum activity | 185 MBq | Exemption limit ×106 for non-fissile isotopes, 200 mg for fissile 235U and 239Pu | 185 GBq, 18.5 GBq per sample | 100 × LL per sample (Swiss clearance limit) maximum 10 samples | |
| Maximum dose rate | 0.5 µSv h−1 outside of glovebox, 15 µSv h−1 in contact with sample confinement | None, as long as the annual dose rate of 6 mSv for controlled areas is respected | <0.5 µSv h−1 outside the beamline, <2 mSv h−1 inside the beamline | 0.5 µSv h−1 outside of hutch, 2 mSv h−1 in experimental hutch | |
| Experimental stations | (A) EXAFS with 18-element Ge (Mirion) and Falcon-X (XIA) (B) Spectrometer (Johann-type, five-crystal, 0.5 and 1 m Rowland circle) (C) Six-circle diffractometer (LaB6 (110: 0.013°FWHM) (D) Pilatus diffractometer | EXAFS with Vortex ME4 and Vortex EX60 (Hitachi), xMAP-DXP (XIA) | Spectrometer (Johann-type, 5-bent-crystals, 1 m Rowland circle) with Si(Li) SDD (Ketek) and Vortex EX60 or EXAFS with 8-element HPGe array detector (Mirion), xMAP-DXP (XIA) | (A) High-resolution XRD (B) EXAFS with 13-element Ge (ORTEC) and DXP-xMAP or 13-element SDD (MIRION) with Xspress 3 (Quantum) or Spectrometer (Johann-type, 4-crystal 0.5 m, and 1-crystal 1 m), Image plate (MAR345) or Hybrid pixel CdTe (Pilatus /DECTRIS) for 2DXRD and SAXS | (A) Micro-XAS with 1-element (Ketek) and 5-element (SGX) SDD, Falcon-X (XIA), Eiger 4M area detector or Spectrometer (von Hamos) |
| In operation since | 1998 (ROBL), 2020 (ROBL-II) | 2005 | 2017 | 2009–2010 (below exemption limit), 2013 | 2006–2007 |
| User access | Public user facility (33%), inhouse and collaborations (67%) | Inhouse and collaborations | Public user facility (47%), CEA dedicated time (33%), inhouse (20%) | Public user facility | |
†
VCM: vertical collimating mirror.
‡
Vertical collimation and dynamic focusing in horizontal.
§
VFM: vertical focusing mirror.