Spectra observed towards L1455-IRS1 (see Table A.3 in T_MB scale). Species, transition, and upper level energy are reported in each panel. The vertical dashed line stands for the source systemic velocity measured using the C¹⁸O(2–1) line (+4.7 km s⁻¹). In the ¹³CN(2–1) spectrum the velocity scale is centered on the brightest (8 D²) hyperfine component (vertical blue line) at 217467.1 MHz; the vertical red line indicates the offset in velocity of the fainter component (5 D² at 217467.1 MHz). In the ¹³CS(5–4) spectrum the velocity scale is centered on the brightest (38 D²) hyperfine component (vertical blue line) at 231220.7 MHz; the vertical red lines indicate the offset in velocity of the fainter components (21 D² at 231220.7 MHz; 17 D² 231220.6 MHz; 1 D² at 231220.5 MHz). In the CCD(3–2) spectrum (fourth row) the velocity scale is centered on the brightest (2 D²) hyperfine component (vertical blue line) at 216428.3 MHz; the vertical red line indicates the offset in velocity of the fainter components (0.7 D² at 216428.8 MHz). Lower panel: In the CCD(3–2) spectrum the velocity scale is centered on the brightest (3 D²) hyperfine component (vertical blue line) at 216372.8 MHz; the vertical red lines indicate the offset in velocity of the fainter components (1.9 D² at 216373.3 MHz; 1.4 D² at 216373.2 MHz). In the DCN(3–2) spectrum the velocity scale is centered on the brightest (35 D²) hyperfin component (vertical blue line) at 217238.3 MHz; the vertical red lines indicate the offset in velocity of the fainter components (20 D² at 217238.6 MHz; 16 D² at 217238.3 MHz).