1.
IEEE Trans Ultrason Ferroelectr Freq Control
; 47(5): 1093-7, 2000.
Artigo
em Inglês
| MEDLINE
| ID: mdl-18238645
RESUMO
We describe the operation of a laser cooled (87)Rb frequency standard and present a new measurement of the (87)Rb ground state hyperfine frequency with a relative accuracy of 2.4x10(-15), by comparison with a Cs fountain primary standard. The measured frequency is 6 834 682 610.904 333(17) Hz. An evaluation of the frequency shift induced by cold collisions gives Deltanu/nu(Rb)=(-7.2+/-20)x10(-24) n , where n is the average atomic density in cm(-3). With our present 1 sigma uncertainty of 10(-15), this measurement is still compatible with 0 and about 300 times smaller than for (133)Cs. We also report a test of a possible variation of the fine structure constant at the level of 2.7x10(-14) yr(-1), comparing Rb and Cs cold atom fountains.
2.
Rev Saude Publica
; 11(1): 111-7, 1977 Mar.
Artigo
em Português
| MEDLINE
| ID: mdl-854690
3.
Rev Saude Publica
; 9(2): 125-36, 1975 Jun.
Artigo
em Português
| MEDLINE
| ID: mdl-1081270
4.
AMB Rev Assoc Med Bras
; 18(10): 389-96, 1972 Oct.
Artigo
em Português
| MEDLINE
| ID: mdl-4539361
5.
Rev Saude Publica
; 6(2): 189-97, 1972 Jun.
Artigo
em Português
| MEDLINE
| ID: mdl-4539562
6.
Rev Saude Publica
; 5(1): 51-8, 1971 Jun.
Artigo
em Português
| MEDLINE
| ID: mdl-5315949