Analysis of information sources in references of the Wikipedia article "Boomerang Nebula" in English language version.
adiabatic expansion: 4. DISCUSSION." "2011-2012 & HST: 2. OBSERVATIONS
L156: We have measured a 9 mK upper limit (3 σ) on continuum emission at 89.2 and 145.6 GHz toward the Boomerang Nebula, which is much smaller than the negative temperatures seen in the CO and 13CO J 1–0 spectra, so these must result from absorption of the microwave background, requiring the excitation temperature (Tex) to be less than 2.8 K (Tbb). 3. A TWO–SHELL MODEL In shell 2 (R1,o < r < R2), Tkin < 2.8 K." "1994-1995 :2. OBSERVATIONS AND RESULTS
adiabatic expansion: 4. DISCUSSION." "2011-2012 & HST: 2. OBSERVATIONS
L156: We have measured a 9 mK upper limit (3 σ) on continuum emission at 89.2 and 145.6 GHz toward the Boomerang Nebula, which is much smaller than the negative temperatures seen in the CO and 13CO J 1–0 spectra, so these must result from absorption of the microwave background, requiring the excitation temperature (Tex) to be less than 2.8 K (Tbb). 3. A TWO–SHELL MODEL In shell 2 (R1,o < r < R2), Tkin < 2.8 K." "1994-1995 :2. OBSERVATIONS AND RESULTS
L156: We have measured a 9 mK upper limit (3 σ) on continuum emission at 89.2 and 145.6 GHz toward the Boomerang Nebula, which is much smaller than the negative temperatures seen in the CO and 13CO J 1–0 spectra, so these must result from absorption of the microwave background, requiring the excitation temperature (Tex) to be less than 2.8 K (Tbb). 3. A TWO–SHELL MODEL In shell 2 (R1,o < r < R2), Tkin < 2.8 K." "1994-1995 :2. OBSERVATIONS AND RESULTS
adiabatic expansion: 4. DISCUSSION." "2011-2012 & HST: 2. OBSERVATIONS
