NH3 was observed first in its lowest
J = K = 1 tunneling transition
toward Sagittarius B2 (Sgr B2):
A. C. Cheung, D. M. Rank, C. H. Townes, D. D. Thornton, and W. J. Welch,
Detection of NH3 Molecules in the Interstellar Medium by Their Microwave Emission
Phys. Rev. Lett. 21, 17011705 (1968).
NH2D was detected initially toward Sgr B2 and
B. E. Turner, B. Zuckerman, M. Morris, and P.Palmer,
Microwave Detection of Interstellar Deuterated Ammonia
Astrophys. J. 219, L43L47 (1978).
E. N. Rodriguez Kuiper, B. Zuckerman, and T. B. H. Kuiper,
Deuterated Ammonia Toward the Orion Nebula
Astrophys. J. 219, L49L53 (1978).
15NH3 was observed toward the
Orion Molecular Cloud (OMC-1) soon thereafter:
T. L. Wilson and T. Pauls,
The Detection of Interstellar 15NH3
Astron. Astrophys. 73, L10L12 (1979).
The first detection of a rotation-inversion transition
of NH3 was also reported:
J. Keene, G. A. Blake, and T. G. Philips,
First Detection of the Ground-State JK = 10 00 Submillimeter Transition of Interstellar Ammonia
Astrophys. J. 271, L27L30 (1983).
NHD2 was detected first toward the L134N
dark cloud which is also known as L183:
E. Roueff, S. Tiné, L. H. Coudert, G. Pineau des Forêts, E. Falgarone, and M. Gerin,
Detection of Doubly Deuterated Ammonia in L134N
Astron. Astrophys. 354, L63L66 (2000).
Finally, even ND3 was detected in NGC 1333
and in the Barnard 1 Cloud:
F. F. S. van der Tak, P. Schilke, H. S. P. Müller, D. C. Lis, T. G. Phillips, M. Gerin, and E. Roueff,
Triply Deuterated Ammonia in NGC 1333
Astron. Astrophys. 388, L53L56 (2002).
D. C. Lis, E. Roueff, M. Gerin, T. G. Phillips, L. H. Coudert, F. F. S. van der Tak, and P. Schilke,
Detection of Triply Deuterated Ammonia in the Barnard 1 Cloud
Astrophys. J. 571, L55L58 (2002).
The detection of vibrationally excited NH3
(v2 = 1) was reported in:
R. Mauersberger, C. Henkel, and T. L. Wilson,
Vibrationally Excited Ammonia toward Orion-KL
Astron. Astrophys. 205, 235242 (1988).
The observation of 111 (0+) 101 (0)
ortho transition of 15NH2D with the IRAM 30m telescope toward
Barnard-1b, NGC1333-DCO+, and L1689N was reported by:
M. Gerin, N. Marcelino, N. Biver, E. Roueff, L. H. Coudert, M. Elkeurti, D. C. Lis, and D. Bockelée-Morvan,
Detection of 15NH2D in dense cores: a new tool for measuring the 14N/15N ratio in the cold ISM
Astron. Astrophys. 498, L9L12 (2009).