Relaxation selective pulses in fast relaxing systems

Christopher J. Lopez, Wei Lu, Jamie Walls

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

In this work, the selectivity or sharpness of the saturation profiles for relaxation selective pulses (R^rsps) that suppress magnetization possessing relaxation times of T2 = T2rsp and T1 = αT2 for α∈12,∞ was optimized. Along with sharpening the selectivity of the R^rsps, the selective saturation of these pulses was also optimized to be robust to both B0 and B1 inhomogeneities. Frequency-swept hyperbolic secant and adiabatic time-optimal saturation pulse inputs were found to work best in the optimizations, and the pulse lengths required to selectivity saturate the magnetization were always found to be less than the inversion recovery delay, T1ln(2). The selectivity of the optimized relaxation selective pulses was experimentally demonstrated in aqueous solutions with varying concentrations of the paramagnetic species, [Mn+2], and for use in solvent suppression. Finally, the "rotational" properties of spin relaxation were explored along with an analytical derivation of adiabatic time-optimal saturation pulses.

Original languageEnglish
Pages (from-to)95-106
Number of pages12
JournalJournal of Magnetic Resonance
Volume242
DOIs
StatePublished - Jan 1 2014

Fingerprint

Magnetization
pulses
selectivity
Relaxation time
saturation
Recovery
magnetization
sweep frequency
sharpness
inhomogeneity
derivation
relaxation time
recovery
retarding
inversions
aqueous solutions
optimization
profiles

Keywords

  • GRAPE algorithm
  • Relaxation
  • Saturation profile
  • Selective pulses

ASJC Scopus subject areas

  • Nuclear and High Energy Physics
  • Biochemistry
  • Biophysics
  • Condensed Matter Physics

Cite this

Relaxation selective pulses in fast relaxing systems. / Lopez, Christopher J.; Lu, Wei; Walls, Jamie.

In: Journal of Magnetic Resonance, Vol. 242, 01.01.2014, p. 95-106.

Research output: Contribution to journalArticle

Lopez, Christopher J. ; Lu, Wei ; Walls, Jamie. / Relaxation selective pulses in fast relaxing systems. In: Journal of Magnetic Resonance. 2014 ; Vol. 242. pp. 95-106.
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