We have observed the 70 μm dark infrared dark cloud (IRDC) G14.492-00.139 in the N2D+ J = 3–2, DCO+ J = 3–2, DCN J = 3–2, and C18O J = 2–1 lines, using the Atacama Large Millimeter/submillimeter Array (ALMA) as part of the ALMA Survey of 70 μm Dark High-mass Clumps in Early Stages. We find that the spatial distribution is different among the observed emission from the deuterated molecular lines. The N2D+ emission traces relatively quiescent regions, while both the DCO+ and DCN emission emanate mainly from regions with signs of active star formation. In addition, the DCO+/N2D+ ratio is found to be lower in several dense cores than in starless cores embedded in low-mass star-forming regions. By comparing the observational results with chemical-model calculations, we discuss the origin of the low DCO+/N2D+ ratio in this IRDC clump. The low DCO+/N2D+ ratio can be explained if the temperature of the dense cores is in the range between the sublimation temperatures of N2 (∼20 K) and CO (∼25 K). The results suggest that the dense cores in G14.492-00.139 are warmer and denser than the dense cores in low-mass star-forming regions.

We carried out mapping observations toward three nearby molecular clouds, Orion A, Aquila Rift, and M17, using a new 100 GHz receiver, FOREST, on the Nobeyama 45-m telescope. In the present paper, we describe the details of the data obtained such as intensity calibration, data sensitivity, angular resolution, and velocity resolution. Each target contains at least one high-mass star-forming region. The target molecular lines were 12 CO (J = 1 − 0), 13 CO (J =, and CCS (J N = 8 7 − 7 6 ), with which we covered the density range of 10 2 cm −3 to 10 6 cm −3 with an angular resolution of ∼ 20 and a velocity resolution of ∼ 0.1 km s −1 . Assuming the representative distances of 414 pc, 436 pc, and 2.1 kpc, the maps of Orion A, Aquila Rift, and M17 cover most of the densest parts with areas of about 7 pc × 15 pc, 7 pc × 7 pc, and 36 pc × 18 pc, respectively. On the basis of the 13 CO column density distribution, the total molecular masses are derived to be 3.86 × 10 4 M , 2.67 × 10 4 M , and 8.1 × 10 5 M for Orion A, Aquila Rift, and M17, respectively. For all the clouds, the H 2 column density exceeds the theoretical threshold for high-mass star formation of > ∼ 1 g cm −2 , only toward the regions which contain current high-mass star-forming sites. For other areas, further mass accretion or dynamical compression would be necessary for future high-mass star formation. This is consistent with the current star formation activity. Using the 12 CO data, we demonstrate that our data have enough capability to identify molecular outflows, and for Aquila Rift, we identify 4 new outflow candidates. The scientific results will be discussed in details in separate papers.