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Table A.2

Photoevaporation-, total-, and free-fall lifetimes of observed objects.

Source d OB t photo t expos t total t ff
[pc] [106 yr] [106 yr] [106 yr] [106 yr]
(1) (2) (3) (4) (5)

Pillars    n(H2) ⟩ = 5 × 103 cm-3, r ⟩ = 0.61 pc
1 43.4 8.38 0.92 9.30 0.14
2 46.2 3.77 0.64 4.41 0.15
3 50.4 3.76 0.23 3.99 0.25
4 44.8 2.30 0.78 3.08 0.22
5 30.8 2.84 2.15 4.99 0.23
6 19.6 3.63 3.24 6.87 0.15
7 10.5 0.47 4.13 4.60 0.15

Globules    n(H2) ⟩ = 12 × 103 cm-3, r ⟩ = 0.60 pc
1 26.6 2.35 2.56 4.91 0.16
2 36.4 5.10 1.60 6.70 0.41
3 42.0 6.19 1.05 7.24 0.34
4 11.5 1.66 4.03 5.69 0.12

Condensations    n(H2) ⟩ = 55 × 103 cm-3, r ⟩ = 0.11 pc
1 37.8 3.58 1.46 5.04 0.62
2 37.8 2.54 1.46 4.00 0.69
3 37.8 4.00 1.46 5.46 0.46
4 32.2 3.02 2.01 5.03 0.62
5 33.8 3.92 1.86 5.78 0.77
6 39.7 7.71 1.28 8.99 0.71
7 29.4 2.44 2.29 4.73 0.46

EGGs    n(H2) ⟩ = 22 × 103 cm-3, r ⟩ = 0.11 pc
1 37.8 1.48 1.47 2.95 0.37
2 38.1 1.22 1.44 2.66 0.40
3 38.6 2.04 1.39 3.43 0.27
4 37.1 1.28 1.54 2.82 0.50
5 37.8 1.32 1.47 2.79 0.42

Proplyd-like    n(H2) ⟩ = 15 × 103 cm-3, r ⟩ = 0.17 pc
1 14.0 0.47 3.79 4.26 0.31
2 13.0 0.37 3.88 4.25 0.38
3 11.5 0.76 4.03 4.79 0.29
4 12.0 0.57 3.98 4.55 0.30
5 13.0 0.99 3.88 4.87 0.28
5a 13.2 0.72 3.86 4.58 0.28
5b 13.4 0.62 3.85 4.47 0.29
5c 13.0 0.56 3.88 4.44 0.32
5d 12.7 0.49 3.91 4.40 0.34
6 5.9 0.55 4.58 5.13 0.31
7 6.4 0.34 4.52 4.86 0.25
8 6.1 0.36 4.56 4.92 0.25
9 6.9 0.18 4.48 4.66 0.44
10 9.3 0.49 4.24 4.73 0.31
11 37.8 1.47 1.46 2.93 0.45
12 37.8 0.61 1.46 2.07 0.32
13 32.2 0.11 2.01 2.12 0.33

Notes. (1) Distance to the center of Cyg OB2. (2) Lifetime of object until complete destruction by photoevaporation. (3) Time the object has been exposed to UV radiation of the H II  region. (4) Total lifetime (tphoto + texpos). (5) Free-fall time (Eq. (6)).

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