Becoming a User

This site is OBSOLETE as of 30 Oct. 2017
Please go to the new User Resources site

LCLS beam lines are open to academic and industrial users for scientific research. All research proposals are subjected to peer review and ranked against competing proposals based on scientific merit.

Register and Submit Proposals in User Portal

The first step to becoming an LCLS user is to register in the user portal, and work with your collaborators to submit a proposal. To  learn more about LCLS capabilities, check out the LCLS instrument descriptions and contact LCLS instrument scientists for more details. LCLS experimental stations available to users:

Review LCLS Policies and Guidelines

LCLS aims to attract diverse users and to enable a broad set of important science that takes advantage of its unique capabilities. LCLS has six experimental stations with wide-ranging capabilities. LCLS proposal review policies describe the process that LCLS uses to review, select and schedule experiments.

Review Machine FAQ & Parameters

LCLS has demonstrated FEL operations over the energy range 280 eV to 11.2 keV using the fundamental, with pulse energies of at least 1-3 mJ depending on the pulse duration and photon energy.  Third harmonic radiation is available up to 25 keV at about 1% of the fundamental pulse energy. The pulse length can be varied from 40 fs to 300 fs for hard X-rays, while for soft X-rays the range is extended to 500 fs. Shorter pulses, <10 fs, with a reduced number of photons per pulse can also be provided. The maximum repetition rate of the LCLS is 120 Hz (please note that this may be reduced to 115 Hz at certain time periods).

For users who require a monochromator, seeded beams can provide 2 to 4 times more photons per pulse than SASE beams, and with similar pulse durations and shot-to-shot intensity fluctuations. The narrow seeded line, 0.4 to 1.1 eV FWHM,  for 50 fs pulse duration typically contains an average pulse energy of 0.3 mJ, with occasional shots up to 1 mJ. It is accompanied by a relatively broadband SASE background of comparable total energy. Seeded beams for hard-x-ray operation are available from 5.5 keV to 9.5 keV and can be tuned up from a SASE beam in about 30 minutes.

We are continuing to upgrade the soft x-ray source parameters of LCLS. Soft x-ray self-seeding has been successfully demonstrated across the range of 400-1000 eV.  We are offering its operation during Run 13 with explicit understanding that lengthy tune up time might be needed and that larger contiguous blocks of awarded beam time (24 and 36 hour shifts) will be scheduled in favor of multiple 12-hour shifts.

The recently installed Delta Undualtor has demonstrated variable polarization output including left/right circular on the order of a few microjoules per pulse.  Operation of the DELTA system in Run 13 will be assessed on a proposal-by-proposal basis provided proper diagnostic/instrumentation are supplied by the User group for full characterization of the polarized DELTA output.  M&I and User assisted commissioning proposals will be considered. For more information please contact the Soft X-ray instrument scientists,

LCLS is currently developing a range of two-pulse and two-color operating modes, where pairs of FEL pulses are produced with variable temporal separation, and/or up to 1% photon energy separation, in both the hard and soft X-ray regimes. We will accept proposals utilizing two-pulse and two-color operation.